There are several companies out ther that compare flight prices. You can go to the Travelocity website, Cheap Flight's website, or you could individually check prices on the different airlines on there websites and compare them yourself.
To compare prices for an iPad 2 go to an online website for merchants that sell stuff, like eBay and amazon, and you can compare them there, or at RadioShack.
One may go into car businesses and ask them directly about their car prices and take note of them, or one can go to Auto123, a car review company, and compare the prices on their website.
A good website to purchase and compare prices for an oven online would be to go to either of the following sites www.ebay.com or www.amazon.com for great deals
To compare cell phones you can go to E bay website and/or different cellular phones websites and compare prices. You can also visit Amazon that lets you compare cell phone prices.
The easiest way to compare auto insurance prices is to use an auto insurance comparison site such as Go Compare. Another good website to use is Money Supermarket.
If you want compare prices for a rental car I always use Expedia to price them, and then I go to the actual rental website that is the cheapest and see if I can find them cheaper!
One of my favorite sites to use is Bizrate. When you go on their site, search "compare air conditioning." Many different units and their prices with appear.
To find prices for Chevy Cobalt you can go to edmunds website. You can also look for Chevy Cobalt prices if you go to autotrader website. Autotrader will also give you a Chevy Cobalt near you and you can compare millions of listings.
You can go to the website of Shopper. On this website, you can get lots of smartphone information like price, manufacturer, service provider, etc. You can compare prices and make the best decision.
One can compare prices for the PS3 video game system by going to multiple stores. If you want it new, go to Game Stop, Best Buy, Target, or Walmart. If you don't mind a used system, check out Movie Trading Company or Game Stop.
You can go to shopping.yahoo.com to compare mattress prices online.