I just made a purchase from motherhood.com. Their shipping is a bit on the expensive side, but I got a pair of jeans and 2 tops for $90 not including shipping. They have a huge range of clothes, much better than most places I've found for us bigger girls. Can let you know what the quality is like once I receive them.

I've got a belly band so have just been using that so far and my pre pregnancy jeans. I did get a pair of black yoga pants from Dorothy Perkins but their shipping was so slow and customer service was appalling so I personally won't buy anything else from them. I have also got a pair of lovable yoga pants which are great, though quite a light fabric so chilly in winter. I'm a 20ish pre pregnancy and the size 18/XXL fits really well. Also have a size 16/XL which fits but is much more fitted, so the sizing is pretty generous.