Check with his ISP. My ISP keeps stats. One set is call "Exit Pages", showing what page someone was viewing when they left my site. Sounds like exactly the thing you're looking for.

Hmmm, maybe not. OK, try this: assuming you do have those kinds of stats available, have each link of interest point to a page that just does an immediate transfer to the site of interest. That page would be logged as the exit page and if appropriatly named, would tell him where the visitor was going.

The refresh meta tag looks like this:

<META HTTP-EQUIV="refresh" CONTENT="0; URL=http://www.example.com">
[download]

(This does seem like a clumsy work-around but I think it's workable)