I am working on the Tamiya M3A2 Halftrack and wanted to incorporate some battle damage into it, such as dented fenders, bullet marks, etc. I have been unable to find any basic "how to" articles to help a newbie like me in this area. Does anyone know of any good references for this? :

Thanks to all for your help on this and on my other questions.

Barry,
from a brief look at articles here on site, you might be interested in these 2:

Fixing The Halftrack

and;

Making Replacement Parts From Aluminum Foil

This last one beacuse it's far easier to simulate damage on parts made from foil than plastic.

Hope they help!

Vinnie

Here are a few things you can do with that kit in particular:
In addition to thinning fenders for bending, (a spherical steel cutter works best) you can thin them prior to adding bullet/fragmentation holes. Bullet holes will be very small, but fragmentation holes can be fairly large, and irregularly shaped.
For the armor plating, you can remove a panel and drill holes where the rivets have popped out, or even better, just crack part of a plate completely off and leave a few shattered bits on the ground.
The Tank Workshop Wheel Set would be a nice addition as well. (Better than the photo etched ones, as I've used both) You can then grab the drive and idler wheels with needle nosed pliers and simply snap bits, or whole chunks off.
Leave off one or both front tires, and wrap several strands of fuse wire around the bare wheels. Remove the rubber from the road wheels and delete the tracks on one side. Replace the tracks with four turns of thin kite string, and rust the whold thing using your favorite technique . The tracks were literally rubber bands with cable inside as reinforement. Once burned, all that remains is the cables. You can really have a lot of fun with this one.

Of course seat cushions and wooden stocks on weapons would be burnt off as well.