I pick up a lot of 1-2 dollar historical books whenever I pass by them but I find myself reluctant to read some of them as I don't know how to measure their veracity besides amazon ratings etc, which I don't fully trust
I know theres a booklist here that has specific recommendations, but for those times you happen to run into something interesting that's not on it, how can you determine if it's an accurate book that'd expand your understanding or something that might handicap you with misinformation or outdated theories?
I'd appreciate any help on the general problem of vetting literature or specific critical reviews of War in the Middle Ages by anyone who has read it and studies that field.
Contamine remains a classic though it is a bit dated and schematic (i.e. he presents a very black and white picture of medieval warfare). He is certainly worth reading but there are also newer things out there which question such elements as the ubiquity of mounted warfare, the role of feudalism in military organization etc.
In terms of how to vet a book in a larger sense, /u/a_guile's point about whether a book provides sources is an excellent place to start. Footnotes are a big win (or end notes), a bibliography that includes both secondary and primary sources is also a very good sign.
Another thing you can look to is who the publisher is. This is not always a sure thing but generally an academic press from a known university is a very good sign of a book's value.
The year of a book is also helpful, as I noted Contamine is dated, the original French is from 1980 and the translation is from 1984 (incidentally the fact that it was translated at all is another indication of the books value). This doesn't mean a book is no longer worth consulting, but the older the book the more likely it is that both facts and interpretation will have moved on. 30 years is a long time in the scheme of things, works from the 1960s are now 50+ years out of date.
A great resource if you are looking for reviews that aren't amazon is academic journals. Of course you have to have access to them, but libraries etc have JSTOR, and if you do a search for the book in question you can find reviews by reputable scholars. Contamine, for instance, has several. These can give you a sense of how other historians and scholars in the field regard the books. If there are no reviews that's not a great sign. For more recent books the The Medieval Review is a free web-only resource that puts out reviews every week since 1993.
Likewise, check out google scholar and you can see free reviews and see the number of times a work has been cited. Of course this is still in its infancy, but Contamine has 371 listed citations, which is indicative of how many people have used it.
So yeah, read it, but just be aware that he isn't always super great at nuance. He is painting with a broad brush at times, covering a lot of ground on a very big subject. But he is still a go-to for anyone working on the topic.
Look into the sources, these should be at the back of the book. If it has trustworthy sources it should be fairly trustworthy. If it has flaky sources or no sources it should be regarded as less trustworthy.
It might still be a good read even if the sources are not ideal. But keep in mind that you will probably get more of an opinion of the time than a hard source. Look at Herodotus' Histories, he had unreliable sources and as a result has a lot of myth in his book, but it still gives a great deal of incite into the attitudes and beliefs of his contemporaries.