Hi,
I'm not sure if you've seen this or not, but this is a post from the Kitchen forum. This couple is doing an AMAZING DIY on their kitchen. Their floor tile came from Lowe's and I think it's gorgeous! The link I've posted is from their 2nd posting, because the first got too long, but you should be easily able to find the first post which included the name of the tile I think.
Lynn

Here is a link that might be useful: DIY Floor Tile from Lowe's

That's my kitchen that bestyears kind words mentioned. Lowe's where we live (city of 250K) has a really decent selection of tile that's affordable and the one we used is called Rialto Beige. It's porcelain and was about $2.25/sq ft.

Are you sure there aren't more tile stores? Because in my area, there were probably 3 dozen flooring stores that carried tile [a couple with nothing but] before we were considered big enough to support a Lowe's, and this region probably sees a lower % of tile floors than almost any in the lower 48. We have a few furniture shops that happen to also carry carpet, but virtually every real flooring store has tile, and have quite a few samples on hand.

Driving an hour or two to an area with more selections would be a good investment, just so you know what your options are.

May I suggest choosing based on the COF [cofecient of friction, aka 'grippiness', reduced to a numerical rating-- higher is better] rather than color or size. I'm not saying you can't get a look you love, just make saftey a very big part of the equation. Most tile makers list the COF somewhere on the website, both dry and wet numbers. The wet is obviously more important in a bath.

If you test any samples on your own, be sure to use a lot of water: my sister's tile is all slick as ice when wet. I learned from her mistake, and mine is waaaaay better. My new house will be better still, now that I learned [from Bill V.] what the COF numbers mean.

As a general rule, more texture is better than less, less gloss is better than more, natural stone is less slippery than tile. Unglazed is less slick than glazed, which tends to mean an unglazed through-body porcelain is better than a glazed, whether the glazed is porcelain or ceramic. The unglazed also hides waterspots.

Go with as dark a grout as you can bear: I have a charcoal grout in my back door entry that needs no attention at all: wipe the tile and the grout is clean. I don't find the lighter grouts all that tough, but I don't care if they look perfectly uniform so long as *I* know the lines are clean. Dark grout saves a lot of work for more anal types.

Oh, and to answer your original question [bet you thought I'd forgotten!]: larger tile is all the rage right now, but in a bath I'd go smaller than 12x12 if you can find one you like. The extra texture offered by having more grout lines will add a bit more saftey, and I personally think using sizes that reflect the dimensions of the room work better. For small and simple, you can't beat an oblong [not all oblong tile is 'subway'] tile set in a herringbone pattern.

I got my kitchen tile from Lowe's. Their in-stock selection is not the best, but they have a decent variety of special order tile. I think mine was around $3/sf, Macadamia-something, I can't quite remember.

Tile size seems to come down to personal preference. I think 12x12 works fine in a smaller bathroom, but looks much better if laid on the diagonal. It helps to visually stretch the space. My kitchen has some narrowish walkways and you can see how the 18" tile on a diagonal layout looks in this kind of space.