I think you should move on. Why would you spend A LOT of money to locate him? I could understand if you were searching for a long lost relative or something along those lines, but from what you wrote it seems like the two of you new each other for well under 6 months. Seriously, wouldn't you be a little pissed off to spend money to locate him only to find out he's happy and has a gf? Like others have mentioned if he wanted to get in contact with you he could, and apparently at this point in time he's not interested.