Don't pick up another Christmas gift before getting today's advice on the best places to buy electronics this holiday season!

The December 2012 issue of Consumer Reports  has new ratings for both traditional retailers and online retailers.

The two online retailers who got the highest score are consistently rated as two of the best. They are NewEgg.com and BHPhotoVideo.com. Meanwhile, Amazon.com and Costco.com were in a dead heat right behind those two leaders.

When it comes to physical stores, Costco Wholesale and the Apple store both tied as top contenders. Costco also was named the lowest cost place for electronics among brick-and-mortar retailers. On the other end of the spectrum, Wal-Mart stunk it up as the worst among physical store locations.

And remember, when you get in the store, the salesperson will push you to buy an extended warranty. Don't do it. The math is overwhelming on this point.

During the first 3 years of ownership, the typical failure rate of flat screen TVs is between 3% and 4%. On digital cameras, it's between 3% and 4%. The only category with a significant failure rate is laptop computers.

With the laptops, a lot of that could be user error, i.e. people dropping them. But even so, the laptop failure rate is still on average only 10% during the first 36 months of ownership.

So the math isn't in your favor when it comes to extended warranties.