Actually LOTR made the how to, and it's
sticky'd so it should be easy to find. But thanks for the vote of confidence
Pretty much what you need to do is write the IP+Port of the user you browsed for later use. There is unfortunately no way to save hosts inside Limewire, so it has to be done by hand.
Note: If the user you browsed has a dynamic IP and restarts his modem, there is a great chance that the IP changes. Would be nice if they would implement a way to have usernames in Limewire.