I would second people's recommendations to look at department stores if you're going for black.

If you're set on getting bridesmaid dresses, I ordered my dresses from netbride.com -- they had hands-down the best price on it. They carry a lot of designers, so I emailed them for quotes on a Bari Jay, Liz Fields, Dessy and Jim Hjelm -- they were always cheaper than from a salon.

I ordered Bari Jay 641 in shadow gray for $119:

http://barijay.com/style.php?style=641

The online reviews are good -- I'll report back in July when the dresses actually arrive.

I've found all my online communications with them to be great so far.