tweed can be pricey. generally about 12 to 15 a linear yard. 1 yard by 58 inches i think....
go to a fabric store, they'll have it. also the adhesive you can pick up at Autozone even... look for Carpet, Headliner, and Fabric spray adhesive.
Practice practice practice! Or pay someone else (*cough* me *cough*) to do it cuz tweed is expensive to screw up a piece
i just did half my front interior this weekend... even fabbed bowties in the kick panels.
let me know if you need anything else