Here is one link with some decent photos: http://www.pbase.com/stefan_serb/weapons this site has one or two decent action pictures, but the others are kind of sad in that I have a friend who was there, and it's just....sad.. http://www.digitaljournalist.org/issue0407/richards.html. Here is another one for you www.defenselink.mil it has a few winter scenes as well.
If you google "Serbian Croat war Photos" a bunch of stuff comes up, I'd try to google it under images as well, only type in "Croatian soldiers" and then "Serbian soldiers". Alot of stuff comes up then. It's all mixed up with pics from WWI, but there are definately photos from the Civil war in the 90's there.
Also, try Corbis http://pro.corbis.com/ they have a fantastic base of photos. You have to register (it's free) to view and print photos without there being a watermark on them, but it is worth the time. Just go to Corbis and type in "Battle of Stalingrad", and look at the quality of the pictures that comes back. TONS of WWII pics.