www.tapplastics.com
If you do decide to make an acrylic tank, make sure you do your research first. It isn't like siliconing to plates of glass togther.
You must make sure your acrylic is cut straight and smooth, everything is square and the welding process is a bit more complicated than squeezing a tube of silicone since you ar using a solvent to essentially melt to peices of plastic into one.
I got the oppurtunity to put togther some acrylic stuff witha local guy, and it was fun, but you will need some tools to do it correctly.