Yeah, but for every caucasian English teacher you've met, there are three southeast asian workers willing to take their place for almost half the salary.
JET isn't a company, it's government sponsored, and you have to go through a lengthy (and somewhat difficult) application process to get accepted. And even if you do, positions are extremely limited, and most JETs are placed in very rural areas.
ECC does in fact hire a lot of non-white teachers as well, but as a private eikaiwa school (as with all other eikaiwa schools), you are paid hourly and will have to work to make ends meet. ECC is still doing better than other companies though, such as the infamous NOVA, as well as GEOS which also went bankrupt just last month. The poor, qualified teachers who were at the 100+ GEOS schools that were forced to close are now jobless.
Dispatch companies like JALSS are hiring migrant workers from Thailand, Vietnam, Philippines, etc because they are willing to work for next to nothing; BOEs everywhere are switching to them because of how cheap their contracts are (even though incredibly few of them speak proper English; but BOEs don't bother screening the "teachers"). Only a handful of prefectures like Saitama have wised up and blacklisted JALSS et al from their BOEs.
You can still work directly with the BOE (and skip any middleman company), but then the BOE sets your pay, and can suddenly decide to only hire you for 2-3 days out of the week (forcing you to find other part time work to pay your bills).
If you absolutely must come to Japan and teaching English is the only thing you're qualified to do, it is possible to get your foot in the door. But be prepared to deal with a lot of crap, and don't come with the expectation that your contract will last more than a year (it might, but chances are equally good that you'll be laid off).
Anyway, sorry for getting off topic; I know a lot of people love to think that if you can't do anything else in Japan, you can always at least teach English. But the reality is that the whole English teaching scene has gotten pretty ugly, and is only going to get worse for the next few years. If you're smart, you can make it work, but if not, you will only get burned like countless other qualified English teachers.
There are plenty of IT jobs available in Japan (check japanprobe classifieds or gaijinpot), and depending on what you can offer, some may only require basic conversational Japanese. Look around, too, because some companies may be looking specifically for English-speaking consultants to handle their non-Japanese business.
