I picked this up at the Anderson, SC Target. There was one copy left. It was on the bottom row of their "El Cheapo" endcap.
I had previously checked at FYE here in Greenville, but they no longer stock games of any kind except some old used/clearance stuff and according to them they will not be carrying games of any kind in the future.
I also checked the Targets at Wade Hampton and Woodruff but neither had this game at all.
The game itself is great. The tables are a lot of fun and for $20 I feel the game is well worth it. Plays and looks good on Wii, and the widescreen support is welcome. I think the game looks fantastic (I'm running component on a 1080p 50" TV). It doesn't have the detail or clarity of hi-def PinballFX on 360, of course, but the image quality is very good for a Wii game, and quite frankly, although I like PinballFX and think it's worth it, most of the tables on the Williams collection are superior.