userdb field to scratch variable

["Jerry" <jerry@data-logic.com>]

Could someone help me out with the syntax to get
a userdb field into a scratch variable. This has
totally eluded me all day.

I have a userdb field called rate I need to get into
a scratch variable for setting the rate a particular
user should be charged. Everything works fine when I
hard code this variable. I just can't seem to figure
out the syntax to get a userdb field into a scratch
variable. 

Thanks in advance to anyone who can help!