This is a problem I, and thousands of other online business owners, run into over and over again...

Spending week after week tweaking, perfecting, analyzing, adjusting -- and never actually getting to the product or site launch stage.  Stop messing around trying to make everything perfect.  Get your product launched, and then adjust it as you go along.  Track everything - advertising, sales conversion rates, profitability, ROI, affiliate sales stats - the more you track, the more you can adjust to squeeze maximum profitability out of your project. 

Remember, launch first, adjust later.  Your bank balance will thank you.