I'm currently attempting to write a paper for my History Seminar dealing with German propaganda during the Third Reich and I am finding it insanely hard to find peer reviewed books and articles. I have used JSTOR and Ebsco to try and find peer reviewed sources on this topic, but am coming up empty handed. What are some tricks that you all use to find credible sources that have peer reviews?
Your question has two parts, and if you don't mind I'm going to deal with the second part first:
How do historians ... separate [credible, peer reviewed] sources from those that are not.
The question of how to tell a credible from a non-credible source comes up here a lot, and people have given some very good advice about this in other threads, which I will allow to speak for itself. [Edit: I meant to add a link here, but reddit is giving me "search failed" when I go looking for the threads I was thinking of, will add them later].
Since you're at the "searching catalogs" phase, though, there are definitely things that you can do to separate credible from non-credible sources. And the biggest favor that you can do yourself here is not to get them mixed up in the first place.
A lot of my students make their biggest mistake with their assignment right off the bat: they go to google, they go to wikipedia, or they go to amazon and they type in the keywords that they think will lead them to useful sources. The problem there is that these sources will lead you to a list of books/blogs/articles that has no minimum standard for inclusion, no quality control: anyone can edit wikipedia, anyone can publish a book on amazon, and anyone can start a blog. People can write/publish whatever the hell they want on those platforms, and a lot of people who write complete bullshit on them actually end up being quite popular on those platforms, which means that their work will likely be high on your list if you start by looking at those sources.
The trick here is to confine your searching to databases and catalogs that only pay attention to reputable, academic presses and journals. Do that, and bam, 90% of the "separating" part of your question is done for you. There are whole companies, whole publishers, whole teams of librarians, whole offices full of people whose entire job it is to maintain a minimum standard of academic publishing, and frankly the dumbest thing you can do when you're setting out to write a research paper is to not take advantage of the work these people have done. They're the bouncers who keep the riff-raff out of the club. You need to let them be your primary gatekeepers as far as the quality of the sources you're using.
How? A few simple rules:
So how the hell are you supposed to find usable sources if not through those methods? Here are some of the most effective and massively under-used methods of finding your way to quality sources:
Your school's library catalog: Any major research university is going to have a pretty decent catalog, that uses proper subject headings and is keyword-searchable. It floors me that my students don't use this resource sometimes, because it's amazing. If you're feeling like being super thorough, start by finding the Library of Congress Subject Headings that relate to your topic and then search for those. But that's often not even really necessary anymore. Just start trying different combinations of keywords. You'll often be amazed at what starts coming up, and then you can follow the subject headings of those books to see what else your library has that's related. This being a university library, your school will really only be buying books from reputable publishers and presses. A great way to avoid all the crappy books that might turn up if you typed the same searches into amazon. If your school's catalog/collection sucks, just look up the library catalog of a major research university and use theirs.
Online Databases: You already mentioned two of the biggest ones for history, JSTOR and EBSCO. But there are a lot of others out there - see if your school's library has a history subject guide like this one for other ideas. Generally there are two different approaches here, as with your school's library catalog: you can either try to use these databases indexes/subject terms (some of them use LC Subject Headings too), or you can just try lots of different keywords. And I mean lots - don't despair if you type in "German Propaganda During the Third Reich" and don't get the number/kind of hits you were expecting. Try all the different related terms and combinations that you can think of before you start despairing. Try "Nazi Propaganda," try "German Propaganda 1940s," etc. etc. Be thorough. If you are just not finding what you want/need here then go to the next step for help:
Your School's Librarians: Amazingly, very very few students ask for help when they are having trouble, which is amazing because academic librarians are practically wizards. They can be a huge help to you in a situation like this, and it's their job to help you find the sources you need. If your school has a designated history librarian like mine, go straight to them. Otherwise just ask at a reference desk, or see if you can schedule an appointment with someone who specializes in whatever catalog/database you're working on.
Reference Books: Don't neglect the power of your library's reference section. There are a lot of presses out there like Blackwell, who produce amazing reference books about different areas of history. These things are awesome for giving you a quick-and-dirty intro to a specific area of study, and for their bibliographies. If you're lucky, the essays/articles in these books will sometimes furnish you with a pre-made, pre-sorted, pre-judged list of the key works that you're going to need for your paper.
Bibliographies/Citations: If all this is starting to sound like a lot of work, don't despair, because academic writing being what it is, I have good news for you: All you need to locate is one good, solid book or article on your subject that's been recently published. If you can find one really good academic work about your subject, half your work is done for you. Open up the bibliography or look at the footnotes (especially in the first chapter or two, or in the section of the book that's relevant to your topic) and look at who that author is citing. Bam, you have a ready made list of books/articles that will likely be helpful. Go find a couple of those, and do the same thing for them. Suddenly, you've got a bibliography of your own going!
If you can't locate that perfect, recent book/article that is going to act as your bibliographic primer for your topic, then try an alternative approach: look for an old, "classic" work on your subject, and then type it into Google Scholar. Check the "cited by" list for that work, and sort by date. Bam, you have a list of works which might well be useful, or which might have bibliographies and citations that can lead you to useful works.
And if none of that has worked, the nuclear option: Ask your Professor! Remember, they want you to do well in their class, and it's their job to teach you. Be upfront and honest about having trouble locating sources, and I can guarantee that they'll be able to help. Just don't do it the day before your paper is due. Then they might just be grumpy with you.
For books, worldcat.org is a good index (not everything there is peer reviewed, but if you only click on things from university presses you'll be off to a good start).
If you already have a good general work on the subject the bibliography can be really helpful. General texts often pull from other, more niche works in their synthesis which can direct your research further.
When I'm doing research, I usually search through Google Scholar, which scans a lot of databases, including JSTOR, so you get a larger pool to draw from. Sometimes it pulls from non-peer reviewed sources so you should always check, but it's great to find at least citations.
Also, if you have any books or articles already, go through their bibliographies and try to find those sources as well.
One good place to start looking is Wikipedia and the "further reading" section as well as some of the sources there. Usually the books in the further reading section are actually useful.
With books, check the publisher and the credentials of the author. If a more scholarly organization (Harvard University Press) is publishing it then it is academic.
Like u/kookingpot said, use the bibliographies of other books and articles you might have. If a book doesn't have notes of some type then you probably should't use it
One thing you can look for is a bibliography already made by an academic. Start by searching "nazi propaganda"+bibliography. I see quite a few results you might want to check out, some run by non-profits, some by universities.
Another option along those lines is Oxford Bibliographies Online which your school may have a subscription to. They have somewhat broad headings with a ton of subheadings, so you'll see all sorts of different materials in one of their bibs. They also include a short blurb on the books listed.