Best thing you can do is email the msn address, keep it friendly and see if he replies. I don't think it's right to ask for his mobile number, if he wants you to have it he'll give it to you himself.
I'd also say try and relax about it, I know I wasn't there but I do know that countless people before you have experienced the reality that meeting someone on holiday often doesn't translate into a real life relationship because the nature of a holiday means that people are just so much more relaxed. So i'd try not to pin your hopes on anything happening with this guy, just in case.