If you're able to fit into juniors clothing, this site has a load of little white dresses under $35! They'd be great for welcome dinners, rehearsal dinners, etc. I'm tempted myself, seeing as I can fit into some juniors clothing, depending on cut and materials used. For the price, it wouldn't be that big of a deal to trade out too-small dresses for shoes or something else on their site.
I linked each one to the sale page, so just click which one(s) you like.
They have a lot of great colored dresses that would be perfect for bridesmaids, as well. I can't speak to the quality of the clothing, but I have ordered shoes from this site before & was pleased for the price. Quality was about the same as places like Charlotte Russe, and the customer service is great. The one time I did have an issue with a pair of shoes not up to par (glue stain from the manufacturing process), they were quick to offer a solution, letting me keep the shoes and giving me store credit for the purchase price I paid. All the other pairs I bought were perfect.
Wasn't really looking for wedding/bridesmaids dresses tonight; was actually trying to find my friend a birthday gift. But you can't avoid seeing wedding stuff everywhere once you're planning one! Of course, not like I have to explain that around here...