I am making several props this year with pallet wood. Like Spinwitch mentioned, I got mine free off of Craig's list. They are a pain to take apart as Jaybo stated, they are a pain to take apart. I ended up using a Sawzall with a metal cutting blade to cut through the spiral nails. Once the boards are separated, I use a metal punch to knock out the nail heads.
To screw my props together, I use "Star" drive wood screws. They are self tapping so you don't have to pre-drill the holes. When I got my props assembled, I used a small propane torch to add some more "Aging" to the wood. Here are a few pic of a couple of my pallet wood projects:
Here is a link to my post on them:
http://www.hauntforum.com/showthread.php?t=22770
To screw my props together, I use "Star" drive wood screws. They are self tapping so you don't have to pre-drill the holes. When I got my props assembled, I used a small propane torch to add some more "Aging" to the wood. Here are a few pic of a couple of my pallet wood projects:


Here is a link to my post on them:
http://www.hauntforum.com/showthread.php?t=22770