The birth of the Internet revolutionised the way we shop, instead of trudging round from store to store we can now compare hundreds if not thousands of prices from the comfort of our own home or even handheld device. It has never been easier to find, compare and review products than it is today as online retailers vie to gain our attention and offer competitive services.

As more and more people gained internet access in the late 1990's a number of early shopping portals were launched which cataloged products from listed retailers. Nowadays we have much more advanced Comparison Shopping Engines (CSEs), updated in real time, where we can compare prices, review products and access a range of services aimed at giving the consumer a multitude of choices.

We have put together a list of the top ten Comparison Shopping Engines for 2011 with the help of CPC Strategy. CPC Strategy compared merchant support standards, average price conversions, CPC cost per sale, merchant tools and revenue to support consumers in making the best choices.

The number one Comparison Shopping Engine for 2011 is Google Product Search. Retailers can list products for free and can upload manually or in bulk via FTP.

The second best Comparison Shopping Engine for 2011 is NexTag, which is also voted the best paid shopping service. NexTag is a Cost Per Click (CPC) price comparison service and consumers can search for a range of products and services including travel, financial services, autos and real estate.

PriceGrabber is deemed the third best Comparison Shopping Engine for 2011 and is a CPC service. Consumers are able to access unbiased reviews about the product they are buying, along with the reviews on the seller.

Amazon Product Ads is voted the fourth best Comparison Shopping Engine for 2011 and is also a CPC service. Merchants are able to list their products on Amazon from their own website.

The fifth best Comparison Shopping Engine for 2011 is Shopzilla which is a CPC service. Shopzilla is an easy to use comparison service and merchant's products can be displayed on a number of related shopping affiliates.

Bing Shopping is the sixth best CSE for 2011 and is a free service. Merchants and retailers can list products in bulk which will be displayed across MSN Shopping along with other relevant Microsoft services.

Shopping.com is the seventh best CSE for 2011 and is a Cost Per Click service. Shopping.com is owned by eBay and offers consumers a host of easy to use tools along with unbiased products reviews.

The eight best SCE for 2011 is Become.com, a CPC shopping comparison service which allows consumers to research products and compare prices and items from a host of online merchants.

TheFind.com is a free service and was voted the ninth best Shopping Comparison Engine for 2011. TheFind.com list products by brand crawlers are used to keep items updated and active.

The tenth best Shopping Comparison Engine for 2011 is Pronto.com, which is a Cost per Click service. Users are able to search and compare products and access a range of comprehensive tools.