Hey there,
That is my room.

You almost had the name right, they are called "Puzzle floor Mats." I got mine at Sams club for $15-17/pack. That was the cheapest that I found them. They are 2 feet square and you get 8 to a pack. The keep them in various places in the store, but the last I saw them they were over in the home/hardware area.
Other people have gotten theirs at Target and Dick's Sporting goods. For various prices. Here's a previous discussion about different types of floors:
http://69.0.137.118/dc/dcboard.php?...ic_id=46462&mesg_id=46462&listing_type=search
I needed 3 packs to do the whole room. The one side is black and the other is either red, blue, yellow or green. I tried the color side and it was just too bright! Also I found (and others mentioned also) that the color side had a weird coating/film that made my shoes a little slippery, but the black side was just fine. Others have also mentioned that having the edges either butting up against something or putting weights on the corners helped them to keep the mats from moving.
Pinky (hippahips) has some beautiful wood-looking ones (
www.greatmats.com) that I would LOVE to have, but I'd alread gotten these. DH agreed next time (since they cost more), but I think it'll be years before mine wear out! Which is a mixed blessing I guess.
Sorry I probably just told you WAY more that you wanted to know, but I like to be thorough. Hope this helps!
Nadine
~~Happiness is an Attitude~~
http://www.picturetrail.com/gallery/view?p=6&uid=3517754&