The Spencer's Gifts in Westminster Mall just received their shipment of SP Dolls today and they were close to selling out already.
I bought all 4.. Only $19.95 each (including Cartman who's about twice the size of the rest) .. They are very heavy duty, and their shoes weigh a ton. The dolls are about 12" tall and appear to be different than the plush ones that the Comedy Central website is offering.
The lady there said that talking ones are on the way as well. My favorite part of the Kenny doll are the drawstrings on his hood. I was surprised at how much detail they put into them.