Earlier quoted context omitted.
As someone who is currently living in Japan, but only working remotely for companies in the US/UK I'm kind of interested to know how you find work here? Is it hard to get contract work? Where do you look? What is the pay like?
Personal contacts, recruiting agencies, job boards (but not craigslist). You're probably better off working for companies in the US/UK. Freelancing is not as common as it is in the US, large and mid-sized companies much prefer to deal with other companies rather than individual freelancers. But you seem to specialize in relatively rare skills, so you might have better luck freelancing than the average web developer.…
Yes, there is freelance work in Japan, but a look at any job board will show that tech salaries are not as high as US/UK jobs. In my experience that seems to affect freelance rates.
I do a mix of US and Japanese freelance work. Personal contacts are the big one for me. Without high level Japanese you may be limited to the foreign tech community.
That community is small but it still can take some time to build up a network. Took me about two years here until I started to get a good amount of Japanese freelance work.
You may both be aware of it already, but if not, the Hacker News Tokyo Meetup is as good a place as any to start: http://hntokyo.doorkeeper.jp
For me the biggest advantages of local work are working with people in person (I got tired of remote only work), and the untapped opportunities in web and software from the US/UK being ahead in those areas.