[Xentron]

I've been thinking this over for months now.
Never really finding the exact answer to my questions to put me at ease.

I am a college graduate from Europe who started working just a month ago.
However I am pondering of studying in Tokyo after a brief vacation next year in Japan.
I was hoping it is possible that after I have stayed a month for some relaxation to continue living there for some time.
I will be arriving with 4 friends of mine who are all interested in Japan but unfortunately have school to return to here in Europe.
That would mean that I would be the only one to remain here in Tokyo.

That being said does any one have any experience with this?
First staying as a tourist and then study in Japan?
Is it possible to extend my visa because I am studying in Japan?
Also how are your experiences with the locals?
I'm guessing it will be hard to become friends with local Japanese men/women?