List of merchant accounts

Hi everyone, I really am a noob when it comes to ecommerce and a client of mine is looking to have this feature built into her site for the sale of online gift certificates.

Does anyone know of a list of merchant accounts/gateways and their prices? Some kind of comparison chart I could use to devise the best fit for my client. Are there any that just charge a flat fee as opposed to a percentage?

Any article/tutorial/comparison that you know of would be greatly appreciated.

Thanks again.

JPG

This is the tool I used, it shows you the best plan based on your type of business, average monthly sales volume and average sale. Saves you time in comparing plans.

http://www.creditorweb.com/credit-card-processing.html