Hit lists: finding the right list service means sifting through numerous options. Tips on finding the best one for you.

There are a host of companies that provide customer e-mail lists: Digital Impact, MessageMedia, NetCreations, yesmail.com, 24/7 Media, DoubleClick and TKL Interactive, just to name a few. But with so many companies out there, how do you know which to choose?

Keep the following pointers in mind while searching for a good list and a reputable provider:

* Look for "opt-in" e-mail lists. The success of an e-mail campaign depends on getting the right addresses. You can do that by ensuring that clients want to receive your e-mail. The key is to look for a list consisting entirely of people who have "opted in." Opt-in means customers have requested, usually by signing up at a Web site, to receive information electronically. Some direct e-mail providers even offer "double opt-in" lists, which means customers signed up to receive information, then later confirmed they were still interested.

* Ask about one-time use. Reputable e-mail list providers rent lists that are restricted to one-time use. This protects the privacy of the customer and ensures that the purchaser receives a reliable list. Be wary of any company that sells, rather than rents, its lists. Avoid sold lists, known as "bulk" e-mail lists.

* Find a list suited to your needs. Most list providers organize their lists into categories of interest. For example, "families with young children" or "active seniors" might be appropriate categories for aquatics facilities. The more detailed the category, the better chance it has of reaching a specific target audience. If you don't find a category that fits your needs, consider looking for a different provider that can better tailor its lists.

* Know the source. Some e-mail marketing companies will provide the list of Web sites from which the e-mail addresses originated. To protect customer privacy, companies won't divulge which particular e-mails were gathered from which particular sites. But an overall list of the Web sites the provider uses to obtain e-mail addresses can be ...