Nice to read your post,
I've converted some rare 80's vinyl into Mp3 myself.
Now beeing a PC user and not knowing Mac's I can't help you with programmes but perhaps you'll find something usefull here:
http://www.audiotools.co.uk/
The setup I used to get a good wav on HD was:
A decent Pickup with Moving coil element
A Alcohol-Destilled water-washing up detergent mix to put on your LP for better Contact (clearer sound)
And I used a Graphic Equaliser (hardware) inbetween Amplifier and soundcard, so you don't need to mess with software to get a good sound
Good luck !