Log files can give you valuable information about the shopping and surfing patterns of your customers, telling you how they found your site, which pages they visited, and who bought what. With careful tracking of the data generated by your log files (especially over the long-term), you can figure out which advertising and marketing tactics are the most successful with your customers. Information like this is valuable because it can tell you where to reinvest and how to change your media-investing tactics based upon what's performing and what's not.

    One popular way to determine what marketing leads customers to buy your products is to track the sources of your sales leads all the way through to the order. Direct marketers have been doing this for years, long before the Web came into being. You'll find source codes on almost everything they send out: postcards, coupons, the backs of the glossy catalogs, and that "address your letter to department ZX321" thing they do. By assigning a unique code to each coupon or postcard, marketers can keep track of which placement yielded the most customer interest. ("The coupons we ran in Young Miss did much better than those in Concrete Monthly.")

    You can do the same thing on your site. If you know the source of the lead, the customer who responded, and the orders that customer placed, then you have a gold mine of data with which to determine your ROI (return on investment). More important, you can improve upon it by fine-tuning both your marketing and site design.

    Do users stop clicking once they hit a certain page? Perhaps that page needs to be simplified, rewritten, or even repositioned to make it easier for your customers to get to the key part of your site: the bottom line.

    To make sure you're using the most cost-effective marketing for your site, you must not only determine which ads are generating the most orders but also quantify a return on that investment. You may find that your direct-mail campaign is bringing all kinds of visitors to your site, but they're not buying anything. At the same time, a banner ad may attract only a few visitors, but those that do come to your site via the banner ad tend to make purchases. Which form of marketing is the most cost-effective? To find out, take a closer look at how much money your site's making and how much you're spending.

    To evaluate the cost-effectiveness of specific advertising, let's take one last look at our beloved ramforless.com.