www.nydancewear.com will make any style leotard in a thong-back, cotton-lycra or lycra. Ask them for their catalogue. Most guys I know who have ordered from them have been very satisfied with their service.
I used to have this little old Polish lady seamstress who would make my dancewear, or customize it per my requests. She could fit my dancebelts to a supreme fit! And if you can imagine standing still while a little old Polish lady puts pins into your dancebelt, moving "things" around, it may sound "freaky," but it was worth it (and she was very professional). Unfortunately, she passed away. However, there are many sites that will custom make dancewear to your specifications, although it may cost a few extra bucks. I'd bet there is a seanstriss in your area who would make what you want.
What do you want? A unique fit? Unusually-patterned fabrics? You can find it. The little old Polish lady made me this great unitard in leopard fabric I bought in a specialty fabric shop in NYC! There's also the site www.renaissancedancewear.com that custom makes stuff at a reasonable price.
There are other sites that will custom make sportswear. The problem with some of these is how much you want to spend. I know one that makes a complete body unitard in a ruberized fabric, but it can cost almost $200.
You just have to look around. www.dancer.com, under their "Dance Links," "miscellaneous resources" has links to many dancewear sites as well as costumers. www.renaisancedancewear.com has great links, too.
If you want further advice, email me. balletboy[/i]