Certain Gap stores carry maternity. I just picked up dress pants, jeans, a dress, and a shirt in-store. The best part was that the pants were 50% off, and the dress was only $14 due to multiple mark downs. Usually Gap Maternity is in a store that sells Gap Kids/Baby. Also, nothing wrong w/ ordering online. Many of the items you can return in-store.
I'm a Gap maternity devotee. I haven't been able to find anything as quality at the price point Gap offers, especially when things are on sale. I find that most other brands are over priced and low quality.