I use a lot of different sites to try and snag deals. I am a chronic researcher and find it hard to make purchases without researching them for weeks, sometimes months, on end.

I find the deal using:

Slickdeals – One of the main competitors in the deal finding segment. They post the main, or “slick”, deals on the front page. They have coupons listed, as well. But the bulk of the deals are posted in the forums. From free magazine subscriptions to FAR (free after rebate) electronics to heavily discounted baby food… they have deals for everything. Link

Fat Wallet – Just like slickdeals, they have deals on everything in their forums. Slickdeals and Fat Wallet are notorious for disliking each other, but more often than not, deals are shared across the sites (it IS an open forum, after all). One of bonuses of Fat Wallet is the cash back program. For example, one of the participating vendors is Lenovo and the cash back rate is 3%. If you buy a laptop for$1,000 (which is probably valued at much higher if you are buying it off of one of these deal sites since they frequently stack coupons!) you will get an additional $30 back! Link

I research the company using:

The Consumerist – If the company is notorious for bad products or bad customer service, I want to know. And on the flipside if the company consistently offers amazing service, they may be worth the extra buck. Be careful, though, as the Consumerist is sometimes very sensationalist. Read with common sense! Link

Reseller Ratings – Good for online retailers which is very important with the emergence and domination of e-tailers in some segments. Is the site legit? Check reseller ratings! For example, Newegg.com has a 9.74/10 lifetime rating. I think they are a safe bet.  However, 1SaleADay.com has a lifetime rating of 3.85/10. Sometimes when I find an exceptionally low price on an item it becomes clear why it is so cheap after looking up the e-tailer. Also, the fact that they list 6 month ratings and lifetime ratings lets you see how the company is trending  (up or down).  Link

I then research the product using:

CNet Reviews – I find the reviews on this site are usually pretty thorough and balanced. I have looked up a few items that I already own and they were pretty accurate. Link

Epinions - If you would rather get feedback from users instead of professional reviewers, I like to look products up on epinions. The key is distinguishing between bad reviews and bad products. ie “Laptop broke after my son spilt water on it!” Bad review. “Hard drive failed on three separate replacement models.” Bad product. Link

Amazon - Amazon is so popular that any item you want to purchase you can find on there. And any item on there that is common enough has usually been reviewed by users. Same thing applies about distinguishing between bad reviews and products, though.
And, of course, Consumer Reports – Who could forget them? Sure, I may not agree with their choices all the time. But they have rallied against extended warranties for years. And being that I worked at Best Buy, that is a noble stance they take. Link

Conclusion

When all is said and done doing these three steps will save you money and frustration in the long run. The key is to get the best product for the most competitive price NOT to get a similar product of shoddy quality at the best price.

Feel free to suggest sites that you use! I love to be an informed shopper :D