the best retail place to buy acrylic is Interstate Plastics, because the guys there are very friendly and OK on the prices. THe problem is they can cut the acrylic for you but they don't have a jointer. Regal has a jointer but they are not as friendly, prices are OK too.

I buy all my acrylic wholesale but when I get it I buy over $500 of acrylic at a time. This is why I can build my tanks and refugiums so cheap. I buy the acrylic at about %50 less than Regal.

I can get individual pieces of acrylic for those of you who want to experiment with building refugiums and small tanks. Just send me a PM with the dimensions of the pieces and I can give you a price.