One of my favorite online shops when I was planning my wedding was the Nordstrom Online Wedding Suite. I would search forever for things like a hair clip, faux fur wraps for my attendants, a clutch that matched the style of our wedding, the list goes on and on. After a lot of searching on the internet, I always came back to the Nordstrom site. I was able to get the items I needed quickly and at reasonable prices. The best thing with Nordstrom, if you change your mind (and come on, what bride doesn't change her mind now and then!?!), they take returns without any fuss.

They also have some great dresses, including shorter second dress options, and jewelry, so I highly recommend checking them out. 
 
Cheers,