IM desperate to add a friend cos im a loner and it depresses me to look at my friends list and find nothin ...nothin i tell u nothin!!!!!!! AHHHHHHHHHHHHHHHHHHHHH!!!
If I were dumb, I would percept that as 'Instant Messenger'. Just pointing it out...
If you know the user name exactly, then follow what Gantic said. Otherwise Google it (Advance Search will save your life here) or use this custom search. It's an AG user search, only problem is that comments get into it too.