Like 50 million other people I've been trying to find a Wii. The local Wal-Mart seems to have them occasionly, but the problem for me is they get them in on a weekday in the morning when I can't go so I had to resort to using the internet.
If you're searching for one check out WiiTracker. It checks all the major sources, lists when they have them in stock, and has a timer that tells you how long its been that they've had them in stock.
I would watch out for the bundle deals. To me (an admitted old fart) they seem to come with games I'm not interested in.
Now to work on my Wii boxing skills.