In the Resource Center you will find a mod called "Random Record Mod"
You might also want to search for "Random Search" to gather all related threads. Here are a few you might want to check out: (these references may be prior to the final mod being written)
calling random mod from within a sub routine
http://gossamer-threads.com/perl/gforum/gforum.cgi?post=14880;search_string=Random%20Search%20Mod;guest=428016#14880
Random Search Mod again!
http://gossamer-threads.com/perl/gforum/gforum.cgi?post=3359;search_string=Random%20Search%20Mod;guest=428016#3360
Unoffical DBMan FAQ
http://creativecomputingweb.com/dbman/index.shtml/