As everyone else mentioned its a challenge to find an experienced developer willing to work for equity alone. The longer you have worked in technology, the less likely you are going to be interested in an equity only deal.

That being said, if you idea is patentable and you are able to secure a patent on it, that would make an equity deal (if it included partial patent rights) much more enticing. If your idea isn't patentable your best chance of getting someone interested in an equity deal is to go after entry level developers. They maybe more willing to take a risk as they build their portfolio and get good real world experience. Craigslist is definitely an option for reaching those sorts of developers, as are developer focused meetup events, and of course college message boards.

Hope this helps!