I want to buy Dance Dance Revolution for my Wii. What do I need to buy? The DDR game? Do I need to buy a mat, as well? Are they sold together or separately? Where/how do I buy that and how much will it cost?

They are sold together. The price is about $50 to $70 dollars because of the mat to dance on.

You can get it at target, walmart or (sometimes) costco.
the game and dance mat come together, and it is usually $70.

Well . I have the game and personally it is really good and it is a really good workout . 9/10 for me (:
If you already have a DDR mat then you can just hook it up to the wii and use it , so you don't need to but another one . On the other hand , if you don't have a mat already , then you can buy one seperatley or with the game bundle . The game and the mat can be sold separatley and in a bundle .The bundle costs 60-70 dollars . The game itself is 50 dollars while the mat alone costs about 20 dollars .You can find the game at your nearest Gamestop, Costco, Wal-Mart, or even BestBuy . Hope you enjoy the game ! (:

I got a free Wii from this site, I highly recommend it!