Shopping Portals: Get Money Back
There are various shopping portals online that give you money back (some percentage) for shopping through them. Two of my favorites include Ebates and BigCrumbs. All you have to do to get paid is complete a purchase transaction through the link to the merchant on their site. When doing price comparisons on the same item at different sites, take into account the percentage back you can get through these sites.

TIP: BigCrums includes eBay on their merchant list; just be sure that you use their link to place your original bid.

Shopping Comparison Sites
Check out shopping comparison sites for a quick comparison of prices. Basically, these sites are search engines for gathering prices of products from a variety of merchants. Enter the product’s model number if available, and be as specific as you can about its features. This way you can be sure you are comparing the same product. Examples include PriceGrabber.com, MySimon.com, and Shopping.com. Also, RoboShopper.com will do a meta-search of several comparison sites.

Discount Shopping Sites
There are general discount sites, such as Overstock, where you can find deals on almost anything. They get excess merchandise from other retailers and sell the merchandise to you at bargain prices.

Coupon Codes
Check coupon sites for current codes that can be used for your purchases. These codes can be by merchant or by product, so be sure to search for both. These coupon sites lead you to retailers, rather than selling you the merchandise directly. You can find relevant coupons by searching on Google for the merchant/product name AND (coupon OR promo*) AND code.

Auction Sites
Try auction sites, such as eBay, for great deals on used (or sometimes new) items. Just be sure to read the description carefully and ask any questions of the seller before you buy. Also, check out the seller’s feedback.

Beware of Fees
Be sure to factor in shipping & handling fees when comparing prices. Some sites low-ball on the published price to attract more buyers, but tack on excessive fees.

Buy from a site that does not charge sales tax in your state, if possible. Online shopping is tax-free if a merchant does not do business in your state, so be sure to factor that into your price comparisons.

Check the site’s return policy before buying. Beware of limited return policies, or “restocking fees.” Also note who will be responsible for return shipping.