If you're confident enough in your ability to convert, try guaranteed traffic. It's relatively cheap, and you choose how much to spend. I am a freelance web designer on the side, and have offered this to a few of my clients. It will generate the traffic guaranteed. You need to make sure your ad is well designed, and you are really selling your product fast. I resell through one of the larger companies and they have a great program.
http://www.trafficaccount.com . If you dont have the in-house resources to design the ad, they design it free.
Pantitude
http://www.pantitude.com