Anyway to get an answer phone message off of a mobile/cell phone onto my Mac?

this may be a bit lo-tech, but you could try turning the volume up on the phone and recording it through a mic. it might work
I would call up your cell phone company; see if you can access the message server over the web, or if they could e-mail you the sound file. I'm assuming they record the messages to servers...
Thanks, I did the mic thing.

It was for a scam baiting thing I did... I got the scammer to call me, and at one point, I said "Do you love me?" he replied "er... yes?" and then I said "Sweet!" and basically played around, lol.