Greetings, I am new here. :)
I am working on a history thesis for my school, and the topic is the development of military technology during the early Middle Ages, (Probably, from the fall of Rome until the Battle of Hastings, but I will probably have to focus on a more specific period,) and it's effect on different civilisations and vice-versa.
This topic is considered very rare and original in my school. Therefore, there are not many people who know much about it, and there are few (if any) books about it in the school's library. That is why I decided to ask for help in these forums.
Does anyone know of good books, articles or other websites which can help me with my project?

"Guns Germs and Steel" by Jared Diamond might be a good general book to start with.
http://en.wikipedia.org/wiki/Guns,_Germs,_and_Steel

I doubt you could do justice to the subject in a single paper though. Perhaps you could narrow your focus a little - weapons, armour, equestrian, architectural, logistical, etc.

I'd second Dan on this one. The topic is so broad you'd need more than a PhD thesis to cover it.

Describe the paper some and maybe we can give you some game plans.

RPM

An example of such an interesting sub-topic would be the stirrup controversy:

http://www.fordham.edu/halsall/med/sloan.html

Of course, behind that article is a corpus of several pretty hefty books and highly technical theses, but it should be able to show how a big topic like this can be abstracted/summarized into a form accessible to the average reader without specialist kniowledge.

Thank you for the replies! I will read this more thoroughly when I will have more time, but the book seems just right. (Especially since I did not focus much about the era and civilisations.)
Indeed, I should have explained it before - I believe that the thesis should be about forty pages long, based on a research question, and that it should contain several (I guess that about five) episodes, which should be determined before I really start working.
I also have about one and a half years to complete the work, and it should be based one at least five different sources. I will probably be more focused on the topic in Tuesday.
And again, thank you.

(P.S: I never saw a spellcheck button in any forum before. This is a great addition!)

I bought a nice little book in France recently which covers that subject. It is just a small 130 pages title, but there are a lot of pictures from the medieval era.

"L'art de la guerre au Moyen Age" by Renaud Beffeyte. ISBN: 978-2-7373-5039-9