How do you walk that line when trying to mine information from the Web? Some data-mining shortcuts, such as scraping data off of social networking sites, are obvious options. But taking such measures can get you kicked off a site for violating its terms of service, or at the very least it will incur the wrath of your customers.

Here are some simple, nonintrusive methods to track your loyal customers, build your contact lists, and otherwise analyze data to learn about potential opportunities online.

You have several ways to generate your own customer lists. One is to write a white paper, post it on your site, and then legitimately collect contact information from anyone who wishes to download the white paper for free. As long as you ask for the minimum of personal information (name, e-mail address, contact phone number), most people will oblige. You could use the same technique to sign people up for a monthly newsletter. is a free service that allows you to send up to 12,000 e-mail messages to 2000 recipients each month. Or, you can post a survey on your Website that collects respondents' contact details, using a service such as SurveyMonkey.

Another way to generate a contact list is to use social networks within their terms of service. You can legitimately . Using names, you can search for contacts and request that they join the Facebook fan page. By sending out friend requests, you allow the recipient the option of following the site or not.