Call for help - plastic bags

I've been working on a project that involves fusing together plastic bags into single sheets of plastic, which will be used as the raw material for a sculpture. I've been saving plastic bags from grocery stores and so far I have a lot of them, but I still don't have nearly enough.

I have lots of white bags already. What I really need are colored bags. I am collecting all colors, but I have a particular need for brown plastic bags.

The lack of bags is beginning to slow down the project, so if anyone out there can donate some bags, please contact me.