I work in IT so to speak, that is I work with computers, as a Sr. UNIX Systems Engineer/Admin with some Oracle DBA work and the market for UNIX/Linux/Oracle is quite strong in Japan.
One thing is to have your name around the industry and you can get work based on your reputation. If you are going to Japan cold, than it might be more difficult.
If you do Windows then you might have a problem there is currently a glut of MS/Windows people so....