Ask HN: where can I find interface designers?

I'm looking to hire someone to do the front end development for my web app targeted at small businesses.

I placed ads on elance, guru and vworker for UI designers but I ended up with a bunch of bids from web designers. I'm looking for the distinctive 'web based software' look-and-feel, not a static brochure site so the bids weren't suitable.

Can anyone recommend another venue where I might find a UI designer? I have a small budget of $1000.

thanks ev