Jpizzle,

You can concatenate conditionals in a single "IF", instead of nesting them, using AND or OR, with paranthesis for priorities (like good ol' maths). For example:

IF( (VAL([Donation]) >= 50.00) AND ( ([Solicitation Code] = "12345") OR ([Solicitation Code] = "0123") OR ([Solicitation Code] = "44444") ), Print, Skip)

You can have as many conditions as you want, and to make it easier the expression editor doesn't care about line returns, so you can do this:

Code:
IF( 
 (VAL([Donation]) >= 50.00) AND (
  ([Solicitation Code] = "12345") OR 
  ([Solicitation Code] = "0123") OR 
  ([Solicitation Code] = "44444")
 ), Print, Skip)
Hope this helps!
Eric.