All of what Cari said except for the garage sales and thrift stores.

I rarely frequent the LQS, especially since I've retired. Prior to retiring, I only bought at the LQS when they had a sale. We have a couple of outlets in the area that carry name brand quilting fabric. I primarily shop there. I also shop at Hobby Lobby fairly regularly and at JAs occasionally. I buy most of my thread, batting and miscellanous stuff at Walmart. My closest Walmart has a terrible fabric department. I only buy online when I need something specific I can't find locally or it's a really good price and quality of "I spy" fabrics.

I confess to buying fabric at estate sales, but most of that has ended up being donated. I rarely find anything at a thrift store.

bkay

I buy from Marshall's Dry Goods. Name brand quilt shop quality fabric $2.98 - $3.98 a yard by the bolt. Or I buy cut yardage from the front of the store for a little more per yard. I live a couple hours from the store. The $1 table has many great finds of yardage, some with flaws but easy to cut around those. Sometimes I find great yardage of name brands for $1 a yard sometimes not. It's fun to look through it! I haven't bought fabric from Walmart since they stopped selling David's Textile fabric. That was really nice fabric. I buy kits and pre cuts from Connecting Threads, Fat Quarter shop, and MSQC. I make the quilts from the patterns I like and the fabric colors I like. I don't custom make anyone a quilt. If a family member asks for the quilt I'm making I give it to them. I do make fun quilts from characters my young grands like. Working on Spiderman and dinosaur quilts now.

Ditto, Cari

Joanns mostly. Followed by quilt shops, HL and WM, depending on where I can find what I like. I have a couple shops I will buy from because they are super nice and their prices reasonable, unfortunately they a 45min/ hour drive away. The LQS near me, not so friendly so I avoid them. I have quilts made from WM fabric that are going strong after 20-30 years and had some with LQS fabric that wore and frayed. It;s not so much where you buy your fabric but the quality of the fabric you buy

Not sure what "constraints" you are talking about, unless cost of fabric. I have collected a nice sized stash so I never need to go out and shop in order to make a quilt. I do shop, but just to add to the stash, usually, and only when I find good deals.

I've discovered a great place to shop for nice fabric... Facebook! There are all kinds of "fabric destashing" pages where you can shop or list your fabric for sale. If you are sick of some of your fabrics, sell them and buy others that you like better. You can find some real good deals there.

I buy from LQS almost exclusively. I buy online from sites I like when I am buying a group of colors and don't need to see them personally to choose the exact colors. I do sometimes use men's plaid shirts from thrift stores. I only buy fusible and interfacing from JoAnns. If I receive fabric in a swap or something and that fabric is scratchy or thin, I toss it.

I don't have any LQS nearby ... nothing at all, even my Wal-Mart no longer carries fabrics ... so I order online. I check sales, and promotional discounts. I make all my quilts to the best of my abilities. I never even consider who will be getting the quilt ... If at the end, it goes to such-and-such a person, so be it ... For me, it's the satisfaction I get from doing it and learning something new along the way. I'm retired, so on fixed income. It's my choice to buy good fabrics that will give me joy in making the quilt.

I'm with Cari and Jane. I shop where and when I can. Price is a huge decider. I have no problem repurposing a 100% cotton sheet from a thrift store. My nearest LQS is 17 km. and honestly, it does not have a huge selection but does offer some nice classes. Shopping online is wonderful until I get to the shipping costs--which can be prohibitive. If I am going 'to the city', I make a point of hitting every fabric venue I possibly can. Those trips are 100km or more one way--yeah I live in the boonies.

I buy most of my fabric from quilt shops - both near home and online. I don't ordinarily make 'gift quilts' any longer except for young members of my extended family. They often get non-quilt shop fabric because I include a lot of novelty stuff not found at quilt shops. Price isn't really a consideration. I have tons of fabric, so only buy stuff for backgrounds.