Customers viewing results on a comparison shopping engine are twice as likely to convert into sales. That means if you haven't already submitted your site and products to the web's top shopping comparison sites, you're missing out on a ton of high-converting traffic.

Essentially, shopping sites are mini search engines that put shoppers in touch with a wide variety of products. Shoppers can search by product category or keyword to bring up a list of products from a variety of merchants. Many shopping engines allow searchers to compare characteristics such as price, product ratings or customer reviews.

Chances are you've landed on one of these sites before, if only by accident. In fact, a majority of shoppers find shopping engine listings while searching on regular search engines such as Google.

The big search engines love these shopping portals because they're:

  • Loaded with millions of frequently updated product listings
  • Chock-full of keywords
  • Valuable to visitors because of their comparison and review features

Because shopping-engine listings rise to the top of the general search engine rankings so quickly, a shopping site can be your pipeline to a top ranking for your top keywords and products--without doing any of the extensive optimization work yourself.

However, it's not enough to submit your products blindly to each site. According to Shopping.com, the top three listed merchants get 50 percent of all clicks, so the higher in the appropriate listings your website appears, the better.

So how do you get your products to the top? Well, each shopping site uses a different set of criteria to list products, so you'll need a unique strategy for each one. The good news is there's only a handful of strategies to learn.

Let's take a look at your top shopping strategies:

  • Pay for an enhanced listing. Some shopping engines, such as Nextag.com, will allow you to pay your way to a top listing. The ones that charge you based on the cost per click usually give you the option of paying more for each click to appear higher in the results. Others will allow you to pay a flat fee for top billing or to display an advertisement for your products across their networks.
  • Compete on price. On shopping sites such as PriceGrabber, Shopping.com and Shopzilla, the products with the lowest prices appear at the top by default. Other sites allow users to sort listings by price even if that's not the default. So in a highly competitive area, you may want to discount your product to attract shoppers. These lowest-price shopping engines work best if you're selling collectibles or hard-to-find items; otherwise you're competing against the likes of Walmart, Sony and Office Depot.
  • Boost your merchant/user rating. At sites such as Yahoo Shopping and Shopping.com, your merchant rating increases as you attract more customers and get glowing customer reviews for your site and products. The higher your merchant rating, the higher you'll appear in the listings. So encourage your customers to review your products and website for you. If that doesn't work, offer an incentive.
  • Optimize your product listings for relevant keywords. Shopping engines such as Google Base and MSN Live Product Search display listings based on their relevance to keyword searches. You upload your product listings to shopping sites through data feeds. These provide fields for you to describe your product in detail. It's essential to optimize your data feeds if you want your listing to appear when someone searches for what you offer.

Each shopping portal has different allowances when it comes to how much information you can include, so read the fine print.

Now that you know the secrets to landing a top shopping portal ranking, let's take a look at some of the biggest and best shopping sites--and what you can do to land in their top three.

Free to list
Google Base --Optimize your data feed and website product pages.

TheFind.com --Optimize your data feed and your own web pages, paying particular attention to your product pages.

Free, but you can pay for better placement or sponsored listings
Live Product Search --Optimize your data feed and web pages, compete on price, boost your user rating.

PriceRunner.com --Pay for better placement, compete on price.

Nextag --Pay for better placement.

Cost-per click
MyTriggers.com --Optimize your data feed and web pages, compete on price (best if you're selling collectibles or hard-to-find items).

Shopping.com --Pay more per click, compete on price, boost your "trusted store" rating.

Yahoo Shopping --Pay for better placement, compete on price.

Amazon Shopping --Optimize your data feed, pay for better placement.

Pronto --Optimize your data feed, boost your store rating, write product reviews of related products.

Ask Shopping --Pay more per click, boost your rating.

PriceGrabber --Pay for a higher listing, optimize your data feed.

Shopzilla --Pay for better placement, optimize your data feed.

Shopping sites are online malls. They attract people who are primed and ready to buy. So they're where you want to be, too.