PR_Tom, I think that if you want to contact an individual webmaster, you need to come to the table with some info, some understanding, and some really good material that will make a difference.
Personal mail should be personal - no stock format, no cut and paste... make the link list owner think you actually checked out their site and made some notes or have some information. Just firing off a form letter is the fastest way to make people feel like nothing.
Now, you might also want to consider looking at your accounts and trying to group them together... link site owners here, TGP owners there, other programs sending exit hits or whatever over there... then you can segment market at least a bit
Alex