Newb alert!

So I've been working with my address book. I've done a FEW VB scripts
for various things, but it's all basically been cut and paste. My
scenario is this.

I work for a small private college in the midwest as a recruiter. I
recruit students from IN, IL, MI and OH. We have a database for all
students, and I get a list of my students from those states that are at
various stages of enrollment status. I imported that in to my address
book, but instead of being able to match certain fields (i.e. GPA, id#)
to the custom fields I have created in outlook, I had to map them to
User1, User2, etc. Is there any way to copy the contents of User1 to a
cusom field ID now? If the solution lies in a script, please help me
understand how to use it. Thank you so much!