haasjj,

A good metal straightedge is one tool that hasn't been mentioned. I have a 5-footer about 3/16" thick that I picked up at a quilting shop. The other thing I use a lot are weights to keep things flat on the board.
The quilting/sewing shop is also the best place to pick up t-pins. They're usually a lot lower in price than you find them at your LHS.

papermache