"start your own business sending email" :)
Wouldn't advise it of course but a lot of people seem to fall for it...
Other searchengines have similar programs to adwords and sponsored links.
By now paying is just about the only way to ever come up in the first several pages of returns on any major searchengine (which is one way I prefer minor ones...).
If you got the cash a small printed ad in an IT mag might work.