I proudly endorse the equipment made by Gearbox Racquetball. I strongly recommend supporting your local pro shop (even if it costs more or is a bit inconveniently placed for your daily commute). If you don’t have a good local pro shop like Recreation ATL, you can try these online shops that I have ordered from successfully in the past.

Go direct:
Gearbox Racquetball Shop

Each of these has quality people answering questions if you email or call them.
Racquetball Warehouse

Dick’s Sporting Goods / Academy Sports / Big 5 Sports have also served my needs well for shoes, headbands, balls, and things which don’t really require any expertise on the part of the sales rep. I only shop at this type of store in person when I can’t afford to wait for the specialty shops above.