There are probably several ways of accomplishing this.
Here is one thread reference taken from the FAQ noted below under the topic "Email" which might help. If not, I'm sure you can find other variations by viewing the threads in the FAQ.
Thread reference:
http://gossamer-threads.com/scripts/forum/resources/Forum12/HTML/002703.html
Topic: Name in email
johnsonny - posted April 20, 2000
If the url above is no longer correct search the forum by topic or the user who posted.
Another reference:
Email field as FROM entry of the e-mail
In my config file I have got a field called "Email" that must be filled out. Is there a way to show the content of the "Email" field in the FROM entry?
The "Email" field is in position 4.
Response by JPDeni:
Use: print MAIL "From: $in{$db_cols[4]}\n";
Unoffical DBMan FAQ
http://creativecomputingweb.com/dbman/index.shtml/