On most Web sites, there is a place during the checkout process to enter a promotional code. Type in the code and your total amount due is automatically adjusted.
Getting the promotional codes is easy and the following web sites do nothing but accumulate and list promotional codes that you can use when shopping online: Coupon Cabin, Current Codes, Naughty Codes.
Promotional codes are distributed by the retailers. Many people who are regular customers of these stores get the codes by e-mail or regular mail. The retailers also hope recipients will pass the information on to friends through viral marketing.
Retailers know posting codes on sites helps attract customers and customers usually spend more on other things. Go see what's on the Internet for the taking!