I've been getting quarter yards for various projects now that I have a boyfriend who is willing to take me to these quilt shops. I have a bunch of purples for a cathedral quilt I want for myself and greens for a quilt I eventually want to make for my boyfriend. Also have a collection of watercolor batiks for my Zelda project, some I haven't even color matched for the project but thought "That might work and if not I can use it". Blacks and whites. Reds and pinks. I spend like $30 max each time and I maybe go once every two weeks at most.
Since I started dating Joe I've accumulated 18 yards of fabric! Actually a little more...there's a couple of half yards in there. Let's round it off to 20. Also not counting the t-shirts for my Kittie quilt. With that kind of fabric that would be enough for a couple of decent sized tops or a lot of smaller projects.
So my method would be going into a quilt store at least once a month, going in there with a budget, buying only quarter yards, and seeing how much fabric I have in two months. $30 will only get me about a good 3 yards of fabric total, but if I do the quarter yards or fat quarters I can leave with 12 different kinds of fabric and I have more variety.
Also, one quilt shop I go to has Bag Lady Day every first Thursday of the month and any fabric you put into their reuseable bags is 20% off. Another store I go to has a rewards program where you buy so much and get something back.