I recently applied to an English teaching agency that doesn't require any teaching certifications -- only advanced English skills. The English part of teaching I have no problems with. But the only teaching I've done in the past has been computer skills with adults.

I'm at a loss as for where to start with English teaching. I thoroughly understand the different components of the language but...I just don't know how to begin planning lessons for both beginner and intermediate Japanese students. I've checked out quite a few teaching resource sites and have some
materials to work with but actually presenting material/information is beyond me, at the moment.

To those currently teaching: what recommendations do you have? I understand that going through certification courses would present me with the knowledge I need but that will be difficult for me to do. I would like to learn on my own if at all possible.
I think that the agency will provide you with sufficient training to get you started, Harry. They do not throw untrained teachers into the fray. You will find, however, that commercial language teaching in Japan (which I surmise that you are speaking of), especially at the entry level, does not require you to do more than follow the lessons in the textbook being used. New Interchange, by Jack C. Richards, is one of the most popular and a typical example of the genre.
That's true -- I entirely overlooked a part of the website that mentioned employers providing training programs.

But on that note, just so I can be a bit more prepared, is there any particular resource that anyone can recommend that would allow me to gain at least a bit of general teaching knowledge? A lot of what I've found on the internet are things like handouts that have material; nothing that can give some ideas about how to present it.
Students: We have free audio pronunciation exercises.
Jeremy Harmer's 'The Practice of English Language Teaching' is a reliable introduction.
Hi Harry
I strongly suggest that you do at least a 40 hr on line TEFL course.
At the very least, it will give you the practical knowledge of Lesson Planning etc.It will aslo give you some credibility in terms of qualifications for the job.
I have just completed the 40 hr course from i-toi in the UK. I have also done the weekend course (20 hrs) and the Grammar Specialist (40 hrs) and will be completig a further 8 Specialist Certificates in the next 2 weeks.
Don't be put off by the hrs - it is totally dependant on how quickly you work through it.

The problem is finding decent employers!

Good luck
Online courses can be good (and probaly quite helpful in your situation) but be careful of buying lots of 'add ons' and extras as Bill is trying to suggest/ is doing. Shop around before buying up with a company such as i to i.
Students: Are you brave enough to let our tutors analyse your pronunciation?
Sound advice from Gina. A solid online course should be all inclusive, and provide you with not only the theory behind teaching English a Second or Foreign language but also with practical ideas and techniques that can help language learning in any situation: in a private lesson; school setting; business classes; missionary work; community project; etc.