Everyday in my life as an account manager I run into clients who refuse to recognize the importance of tracking. If you are one of these people: " I hate you".  At my job I have to ultimately accommodate whatever foolishness I may encounter, but on my Blog; Tracking is everything and inexcusable not to have. If you are building a website using a CMS, make sure you can ad tags to the source code. If you are using a third party shopping cart, then figure out how the cart interacts with tracking solutions. You need to put tags on your cart pages and if they do not allow you to do this, then you are SOL. The types of tracking you should set up for PPC Campaigns is listed in this PPC Tracking Matrix. It will tell you what engines are out there and how to track them. A must as well for your account is enabling Google Analytics you can find more info on Setting Up Google Analtyics here.