Here are some places you can purchase Rubik's puzzles and accessories.
- Rubik's Official Online Site - The official website of the Rubik's Cube. It sells Rubik's Cubes and other puzzles.
- Meffert's Puzzles - Uwe Meffert sells many variations of the Rubik's Cube.
- Amazon.com - Amazon.com sells 3x3x3's, 4x4x4's, and 5x5x5's.
- Puzzle-Shop - Hendrik Haak sells many different puzzles in his shop and is very convenient if you live in Europe.
- Cubesmith - Chris (I forgot his last name) sells replacement stickers for your twisty puzzles. They work very well!
- eBay - It's not a store, but you can find all sorts of things on eBay, including twisty puzzles.
- Speedsolving.com Wiki: Puzzle Shops - Speedsolving.com has a nice list of puzzle stores.