I’m afraid I don’t know Oxford Seminars; so I’m not able to comment on them. Also, I don’t know the Portland area, so I can’t recommend centres there.
I agree with your comment about getting the full interactive experience by following classes in person. On-line classes can be good but they can fall short by not giving trainees the opportunity for observed teaching practice. It’s important to be observed teaching and interacting with students while you are training because you will get valuable feedback that will help you improve. It will also give you more credibility when you are looking for work. However, you could check with the on-line courses whether they have any options for gaining observed teaching practice. You never know, there may be an on-line training programme that has a short face-to-face session where trainees get this experience.
In answer to your questions: to find other courses you could check our Tefl course database at the link below:
You could simply enter TEFL course into any search engine and see what comes up; I guess you’ve already thought of this!
To find out about the suitability of a training programme, I suggest you call up and ask to speak to the head of the training programme. Prepare your questions well; I suggest you include questions such as the following: how are the trainees assessed? Is there an external body that assesses students? How many observed hours of teaching practice are there? What have past trainees gone on to do? Is it possible to speak to any past or current trainees? Is there any job assistance at the end of the course?
Check out the link below for ideas on choosing on-line programmes:
To find out whether the pricing is competitive, you will need to compare prices at various training centres along with a comparison of what they are offering.
Finally, you could put your questions into one of the open forums on this website; some of our users might have studied at centres in your area.
I wish you luck with your new course and career.