They do tend to sell out quickly......
What I did: I approached a salesperson at my local Best Buy and Future Shop and asked when they receive their shipments. For example the FS received their shipments late Thursday afternoon and had the merchandise on the shelf Friday AM. I show up Friday at opening and managed to get one and they still had 10 in the back waiting to be brought out.
Walmart at Square One is always a good place to try. Don't know why, but they seem to get more units more often of hard to find stuff.
Good luck!