So...my only real suggestion is NO strapless dresses - they look terrible on girls that are above like a size 6! I also found Vnecks to be flattering on most body styles
this is the dress that i had for my ladies but in black:
The side gathering thing on it is SUPER slimming on pretty much everyone because it gives the illusion of a waist even when there isn't one (ie ... me!)
I found mine through the designer that made my dress -
Jasmine Bridal - they have a bunch of various collections that come in a ton of different colors, and most can be ordered tea length.
The other thing that I did was i emailed out pictures/prices to the bridesmaids to get their input on what they liked and what they were thinking was a resonable price. Jasmine doesn't have prices listed on their website, so you'd have to call a bridal shop that sells their stuff and ask how much it costs, but they're pretty reasonable. The dress above was about $130
good luck!