I am very interested in making my own units and additions to the game, and was wondering if I could become an "apprentice" to someone who knew how.

Welcome Stockpile. :)

We always need new unit creators.

There are two main methods....3D software programs or by simply cutting-'n-pasting.

I'm afraid that I can't help you with 3D programs (because I can't suss them out myself! :crazyeye: ).
However, have a good read of this cut-'n-paste thread.
There should be enough info in there to get you started, and if you have any problems you could post them there. If I can't help, them I'm sure that there are many others who can.

http://forums.civfanatics.com/showthread.php?threadid=29026

Ive given boulboulgadol some advice, and pretty much started him out...... PM me and I'll try to help you out.