Searching job in Japan is really hard if you don't know Japanese and some little tricks. Generally new graduate hiring for April starts from October or December (in case of 2013) of previous year. I got a job confirmation last month for April 2013 entry. Here I am explaining the steps I took during the job hunting process. First one should register in internet based job navigation websites such as
RIKUNABI,
MYNAVI,
NIKKEI,
GAIJINPOT etc.
The general process is
1. Make account of job navigation websites by filling designated form
2. Search for the company you prefer
3. Bookmark and make a entry
4. Take part in company recruit seminar (会社説明会)
5. Fill up the entry sheet
6. Take SPI test, hikki test and aptitude test
7. If you pass stage 6, you will be informed for the interview (2 or 3 times)
8. If you pass stage 7, you will get 'NAI NAI TEI (内々定)' a formal offer from the company.
9. Company entry as a new graduate (入社)
There are other process of entering company too, but for this you should have meet the criteria set by the company. Before starting job hunting in Japan, learning Japanese may be very useful...