Here are a few of my favorite resources for pottery:

Clayshare - amazing videos. Some free, but totally worth the membership

Clayscapes - love their glazes

De La Designs - love the cutters and stamps

Learn Fired Arts - love the puzzling molds and the leaf stamps

The Ceramic Shop - their selection and pricing is great, especially if you can go pick it up and save on shipping

Diamond Core Tools - the best sanding tools for glaze drips, also great carving tools

Kentucky Mudworks - use their glazes a lot. Would use more of their clay if I could pick it up

Georgie's - love the interactive pigments and the tie dye glazes

Elan Transfers - love her underglaze transfers

Sanbao Transfers - more great transfers