I recently ran an article featuring some money-saving shopping tips. It was incomplete, though, as a reader rightfully pointed out to me. That's because I forgot to mention using discount coupons and codes when shopping online.

For example, I heard from the folks at CouponCactus.com, a site that offers discounts at many online vendors. Just by going through the CouponCactus website, you can get 20% off your purchase at 1-800-Flowers.com, or $50 off certain purchases from iRobot (NASDAQ:IRBT). You can also accrue cash-back rewards on many purchases, such as 2% back on Overstock.com (NASDAQ:OSTK) purchases.

A similar outfit is FatWallet.com, featuring discounts such as an $18 cash-back reward from Netflix (NASDAQ:NFLX), 9% back from various gardening suppliers, 3% back on purchases at eBay's (NASDAQ:EBAY) Half.com, and 6% back from Foot Locker purchases.

At FreeShipping.com, you pay for a membership and can get up to $500 of the shipping costs you pay online refunded each year. There are many merchants on the company's roster, such as Best Buy (NYSE:BBY), Amazon.com (NASDAQ:AMZN), and Dell (NASDAQ:DELL).

Another option you have when shopping online is to do a little detective work of your own. If you're buying Attila the Hun collectibles at AttilaTheHun.net, try typing "AttilaTheHun.net" and "coupon" (or "code") into Google or some other search engine. You might end up with a code you can enter when checking out and paying -- one that will give you a discount, or perhaps free shipping.

For more money-saving advice, tips on great deals, and general investing guidance, I invite you to take advantage of a free trial of our Motley Fool Green Light newsletter service. I think you'll like what you see.

iRobot is a Rule Breakers selection. Netflix, eBay, Amazon, and Dell are Stock Advisor picks. Dell is also an Inside Value recommendation. Overstock is a former Rule Breakers and Hidden Gems selection. You can try out any -- or all! -- of our newsletters with a free 30-day trial.

Longtime Fool contributor Selena Maranjian has not yet made much use of the above sites, but they sure look interesting. She owns shares of eBay, Amazon.com, and Netflix. The Fool has a disclosure policy.