chessmaster 9000 or 10th edt.?

The fact is that fritz+playchess access=fantastic and no other vendor offers that.

CM 9 and 10 are both fine choices. CM9 did in the reigning US champion at the time, unless you're a GM you don't need something like Fritz or Hiracs. CM 9 is the last version available for Mac, thus probably the one you want to get. While analysis may not be as advanced it is good enough to point out blunders.

In case you want the playchess access just buy an old version of Friz on ebay, but keep in mind that playchess does not offer a Mac client.