There are some pretty ropey courses out there and be careful of the bodies that are supposed to recognise the courses as many have basically set up their own body to recognise their courses (try doing a whois search and see who has registered the sites and whether the two share the same address). Ask them to put in writing where their courses will get you a job.
I'd also be wary of people talking about a/the TEFL as if it were a qualification; it isn't, it's an acronym and no more. Also, do you really have to do it online? The lack of teaching practice doesn't work in their favour IMO.
Try here: http://www.icalweb.com/ and Volunteer abroad, TEFL Courses and more from i-to-i have both had good things said about them in other threads.
- For Teachers