they sell bulk packs at most stereo shops, about $200 I think, last I got one was about 3-4 years ago. 40-50 sqft I think (might be wrong, memory is a bit fuzzy) also, you don't have to cover every last square inch like a lot of people do, just get a good majority of your surface area. good tests for where it will do the most good is to tap the sheet metal and find the most resonant spots (big flat areas) Also, don't forget to clean, clean, CLEAN! paint thinner and a red scotch brite pad work wonders