I've been asked where to find fabric by a few people who want to either sew their own swimwear, or they want to purchase their own fabric and have me make them something. Here are a few links to places either I've bought from or my customers have bought from...
My top choice would be Spandex World. I've purchased fabric here multiple times, and have been happy with the quality.
Another place I've bought from is Stretch House. I was pleased with the fabric but was very unhappy with the way they handled the shipping. They asked for all my information over the phone but were unable to tell me what the shipping charge would be. I was surprised to find it was more than the 2 yards of fabric I ordered.
One of my customers bought fabric from The Fabric Fairy. This was a new place to me and I was interested to see what they had. I did not think the fabric was top quality, but my customer was happy with her suit, so I'm happy too.
You can find it in a few stores as well as online. ***but don't expect to see it on a fabric store's website, you'll have to be in store for the first two I've listed and call the third if you don't live in FL*** I've found swimwear fabric in a Hancock Fabrics, a Joann's Fabrics, and there's a place in FL called The Sewing Studio that I used to love going into. They had a full wall holding bolts of swimwear fabric. In more recent years, mom and I have had them send us samples of fabric, since we no longer live in FL. P.S. You won't find swimwear fabric listed on their site but if you call and talk to them directly about printed swimwear fabric they will likely be very willing to help you and even send you samples of what they have...they'll also ask what type of print you're looking for, to help narrow down the search.
Someone shared this fabric supplier with me and I've yet to try them out. They've got lots of lovely prints!! Fabric Depot. This is only their floral page. If you click on 'home' and then scroll down, you'll see on the left hand side of the page, a selection of categories to choose from.
Another supplier is the Spandex House. They have a wide variety of fabrics to choose from!
The tricky part about purchasing online is that you can't feel the quality of it and don't know exactly what you have until you get it.
Also check out this informative post I wrote about different types of stretch fabrics, and swimwear fabrics. Types of Swimwear Fabric.