What Skya said on size. Which is why us girls have to take so long shopping.
I WISH I could just pull things off the rack, but as Skya said above, the size can be radically different between articles of clothing from the same manufacturer.
I have done a small amount of clothes shopping online. I like Victoria's Secret, because they have clothes that they do not sell in stores.
I also like Amazon for shoes. You can search for size 7.5 Wide brown casual flats that are 70% off.
Returning things can be a pain, but some places allow for free returns.