To be honest, despite the low price, you might not have great performance due to the reach. Thus, I recommend you to consider long tail terms on Google/Yahoo which are usually cheaper and have higher CTR.
There are numerous PPC programs available. Those pay per click programs listed below are your best choices because they can deliver sufficient results for most campaigns. There are other PPC programs available and you may find value in them depending on the type of product or service.
Pay Per Click and Cost Per Click Services
PPC Pay Per Click Advertising Programs
Google AdWords Select Cost Per Click
Google AdWords Tips
Overture Pay Per Click
Other PPC Advertising Resources
I'm gonna drop the ultimate Adwords PPC secret right here: Individual sitelinks differentiated, tagged, and tracked within Google Analytics. Yep, I'm serious - that's the secret. Are you doing it? If so, you know what I'm talking about. If not, I bet Simon can help you over the phone, give him a ring at 302-401-4478. You can do all kinds of powerful testing and optimization when you've got sitelink tracking in place and it can really set you ahead of your competition.
Don't go for the lower cost per click. Ultimately what's your goal? Conversion or higher ROI, right? So better use Google and Bing Advertising platform. Use keywords wisely and reach to the targeted audience.