On the other hand, getting hired is a touch difficult, too. Companies that post at websites like Career Cross are mostly looking for fluency and lots of enterprise experience - I never even had any luck getting a reply. Most companies who are looking to hire foreigners also only want people who already have the right kind of Visa (an Engineering Visa - btw, if you have one, GrouponJP is hiring a PHP+Perl programmer to do some marketing analysis stuff).
Things aren't all bad, though. I got my job in Japan by going to one of the Recruit/MyNavi events for Japanese students who had studied in English speaking countries. Recruiters chase down the few foreigners there, but admittedly only one company was actually hiring programmers, and I ultimately wasn't happy there - YMMV.
Some video game and consumer electronics companies also hire foreigners, but large companies usually make all applicants take a test that's difficult for native speakers - I applied to Capcom, but they expected me to be fluent and take the test like everyone else. Of course, that depends on the company - you might have more luck elsewhere, and if you're close to fluent, it's worth a shot either way. Try to apply as a "new college graduate" if you can - there's a whole lot of bias against anyone who's held a previous full-time position, and I'm sure it doesn't disappear when they look at foreigner's resumes.
The other route is through foreign companies - I know at least one person at Google Tokyo who originally interviewed in the U.S. On the other hand, I know someone else at Lockheed Martin who's been fighting to get into their Japan office for years now - so how difficult it is depends on the company.
My advice - do Study abroad, JET, or just a 2~3 month trip; go to Tokyo (I personally prefer Osaka, but the jobs are in Tokyo) and go to the HN Tokyo meetup; if no one knows of any openings, apply to a bunch of foreign companies there; if that doesn't work, get a nice black suit and go to a recruiting event.