About my graduation and work visa

The IT field is blooming in Japan and you definitely have good chances of finding a job. 

It is of course very important that you are here in Japan so companies can interview and hire you, but you can definitely look for opportunities online where they could interview you over skype. But it not easy to find. I don't know how to help you with exact websites but just google something like your profession + Tokyo or your profession + japan job offer, hiring.. check companies websites.. You will definitely find many ways of looking for a job.

To get the work visa you will need a contract and your college degree. it shouldn't matter much that it is not a bachelor degree, but I am not sure. If you'd like to be absolutely sure you should call your local Japanese embassy

I hope it helps!