The Mosaic Tile Co. has all kinds of ceramic, glass and stone tiles, not just little mosaics! They recently moved to this huge new showroom and it's just a pleasure to browse among the displays. They have a lot of tile installed so you can get an idea of what various types look like in place.
Their service is really wonderful, very personal and friendly but always quick. They know what they have and what they can get and they don't waste your time looking randomly through catalogs trying to find stuff.
I ordered two kinds of tile, one with a lot of odd trim pieces, and all of it came within a week or so and was packed well. I plan to go back when we are ready to do more tiling.