if you live near a city with textile mills you can get lots of free samples...and in the 'big-cities' some of the companies will give you permission to (dumpster dive) they literally throw away thousands of dollars worth of great fabrics...every month.
also link up with your local 'free-cycle' another great place to find needed items for free. it is sad but there are numerous (quilters-seamstresses) out there who pass away every year, leaving behind rooms full of (stuff) their loved ones have no idea what to do with...some of them take the time to think about it and sell it...some give it away, some call someone in to clear it out...some just toss it all in a dumpster thinking no one would want all this 'stuff'...i always encourage people to get involved with free-cycle, it gives you a great resource and a place to -pass on- all the things you have no need of.
our local salvation army has a baler, and usually denim, (torn jeans) clothing that they consider to *used* to be sold they bale of and send away...when my mom was making denim quilts she went to them and got a whole bale (about 500 lbs worth) of jeans ... for $20!... back then we thought she had lost her mind! i can not even get my mind around how many quilts they made out of all that denim...and some of the jeans were, just fine...usable jeans too :thumbup:
also check with area churches and small groups in the area(like the senior center- sewing/knitting groups, they all usually have bags or boxes of extra they don't know what to do with.