There isn't a single database for academic works -- even academic databases/search engines such as JSTOR aren't comprehensive. Happily, booklists exist, including the AskHistorians booklist (although ours does mix pop and academic sources).

One thing you might consider doing is searching for comprehensive exam lists -- these are usually lists that colleges and universities generate for people studying for graduate degrees, which require (as the title implies) comprehensive examinations of knowledge in an area. These require a bit of Google-fu, but if there's a particular area you're interested in, you're welcome to ask a more specific question here.

Unfortunately there is no centralized database. And I do agree that many public libraries do a bad job of segregating academic work from non-academic work. I would advise a few things.

1. Check to see what sort of online services your public library has. I've found that many public libraries have access to some combination of JSTOR, Academic Search Primier, or a Gale database (I never use Gale, so being a bit generic here). Each of those three normally has access to a large number of academic articles from journals. JSTOR tends to be about a year to six years out of date (e.g. recent articles aren't uploaded), but has archives going back to the founding of the Journal. ASP tends to have only a year to two year embargos, but has worse past coverage (normally starting in the 90s or 2000s). Finally, although I have never used this, it might be possible that your library has Ebsco's Historical Abstracts, which will give you abstracts (short summaries) for books and journal articles.
2. If you have a particular focus, see if you can find a good encyclopedia. I've been getting a lot of mileage out of Encyclopedia of European Social History from 1350 to 2000. You will need to be somewhat subject specific, because I do not think there is a general "Encyclopedia of History" (contra Philosophy, which has three, two of which are freely available!).
3. Look to places where books are published and reviewed. New Book Network advertises for recently published books in a number of fields (including History). While these might not help you get the history of the field down, they will get you more recent research. Similarly, look to the big academic publishers (Cambridge University Press, Oxford University Press, Routledge, Blackwell, etc.). I follow them on Twitter and they are always advertising some or another book.
4. Look specifically to history reviewers. H-net has a number of free reviews online divided by different subject areas within History. The Institute of Historical Research also publishes freely accessible reviews dating back to the 1990s, I believe. If your library has access to academic journals (through JSTOR, Academic Search Primier, or Gale, those journals should have review sections that deal with books in the discipline. More recently, the journals will label some reviews "Review Articles" which normally means they are dealing with a number of books and are trying to put things in context.
5. [1-4] Can lead to you researching in a very disorganized way, so I second /u/jschooltiger's suggestion to find comp lists. I've found those to actually be pretty easy to find with just "[subject] orals" or "[subject] comp" or [subject] phd reading list" (all without quotes). You might also want to check out syllabi. Different H-Net groups have a history of syllabus contests for both graduate and undergraduate students. H-German has quite a lot and used to have a good recommended reading list, before that feature was removed. H-Ideas also has a few good lists and syllabi. As a final note, a lot of Cambridge papers (e.g. classes) are available for the History Tripos (undergraduate degree) at Cambridge. I generally find the lists quite good and seem comparable to some of the phd reading lists.
6. There are also more generic scholarly bibliographies that cover books and articles. I've used Bibliography of European Economic and Social History but I don't think a new edition has been made in 20 years. You might want to Google something like "scholarly bibliography [field]" and that might help. You might also want to try "handbooks" for different fields. Just Google something like "handbook of German History" and you'll find something. I prefer the Oxford one and they also publish a good number of "short histories" which are there as scholarly introductions of the newest results in the field. Similarly try searching for "Companion [field]" or "research companion [field]" and see what comes up.
7. Finally, there are some miscellaneous resources. European History Online is an encyclopedia of European History online. It is good although will often cite non-English work, which might be a problem for you. Oxford Bibliographies Online can be a useful resource because, in my experience, even if you lack full access, it will normally let you read the introduction and general works sections. The big problem is that there is no Bibliography devoted purely to History and very few institutions have access to all the different Bibliographies. If you are a New Yorker, you're in luck, because NYPL has access to like twenty or 30 different Oxford Bibliographies. You might also want to check out podcasts. History of Philosophy Without Any Gaps has good reading lists for each episodes topics, but obviously those are mostly philosophical. Similarly, Ottoman History Podcast has great reading lists for each episode and because of the position of the Ottoman Empire, can span a number of subdisciplines (urban history, religious history, history of science, social history, etc.).

This is a lot of information! But I thought it might be helpful to you. Feel free to ask me any questions. As you might see by my suggestions, I mostly know German and European History, so I'm not much good outside of that.

The AHR, or American Historical Review is a fantastic journal that publishes articles on a variety of topics. Typicially they are based on chapters of upcoming books, or portions of PhD dissertations. They also review works as well as films, which is a great way to get some oversight and critique of modern scholarship. I am a PhD candidate in Modern European History, but I can ask professors in my dept if you can let me know an area of interest that is beyond my scope.