I've been informed that the CELTA and Trinity TESOL are essentially the same thing. It's just, CELTA has the "Cambridge" name, but the knowledge and experience you gain is practically identical.
I would definately recommend reading as many topics as you can on this forum. Just search CELTA or Online TEFL at the top and there is a wealth of information with regards to the "best" TEFL certification.
to name just a few.
All I can say is that, I'm currently employed full time at the moment, but I've applied for a 12 week part time CELTA course to fit in with my schedule. Not only that, I know in my heart of hearts that I need someone in front of me physically teaching me to learn anything, therefore, choosing the CELTA. Fortunately, my finances have also meant that I can pay for the CELTA course (£999) with little worry. I won't know if this is the best choice for me until I've completed the course, but this was the conclusion that I came to after reading the many, many comments on this forum (and liaising with one of my work colleagues).
If you would like, I'll try to keep a Diary of my experiences of the course, and after completion will also offer my experience of looking for a job in another country too (IF I pass the CELTA).
Hope you're not in a hurry and can wait 12 weeks!
Former Native English Teacher in Hong Kong for 3 years.
British Born Chinese.