I'm a designer who reads HN, and there are lots of other UX, UI and web people on here too.<p>Most good designers won't work on spec, but if you look at print designers interested in jumping to web, you could try providing comparable hours of development for their freelance/personal stuff. I see you're interested in trade/barter, luckily it's your best bet.<p>Also, it sounds like you need a designer who can do front-end, not just any designer. If one of the dev's can pick that up, you've got a wider array of options. While it's becoming more common for designers to know the mechanics of what they're designing for, the good designers who can do front-end are not going to want to work for free.<p>Good luck!
Design is important. You should be offering to make the designer an equal partner.<p>If you can't afford a designer, then launch the product with the design you have, which is not terrible.