Getting minimum qualifications

The Certificate in English Language Teaching to Adults (CELTA) is a good entry level qualification CELTA Cambridge  . In Melbourne Australia a many colleges offer CELTAs. RMIT English Worldwide, Holmesglenn TAFE and others all offer it. This is the most widely recognised pre-service qualification for teachers of English to speakers of other languages.
        You can do the CELTA course in many countries all over the world. e.g. Bali, Saigon, etc... .   If you complete the course in the country in which you want to teach and live, then the school will often help you find work.   You can also  start looking for work and 'sus' out the place as soon as you arrive.  By the time your course is finished you have had time to get used to the place, and find your niche.
On line courses are not as well regarded as face to face traditional courses. 

Japan Exchange and Teaching Programme participants develop strong relationships with local communities through English language education and international exchange activities.

Get your English teaching certificate in Bali, Indonesia.  Cost is similar to what you pay in your own country, plus you get to live in an interesting place :-)
English language institutes in Bali: IALF or EF
see below, from their website:

ALF Bali
Jalan Raya Sesetan 190
Denpasar - Bali - 80223
Tel: 62 361 225243
Fax: 62 361 263509

Trinity College London

Certificate in Teaching English to Speakers of Other Languages

The Trinity Cert TESOL is an internationally recognised introductory qualification for people interested in a career in Teaching English as a Foreign Language (TEFL) or Teaching English as a Second Language (TESL). The Trinity Cert TESOL is similar to the equally well-respected Cambridge/RSA Certificate in English Language Teaching to Adults (CELTA). Both the Trinity Cert Tesol and the CELTA are preliminary courses that allow you the freedom to choose where you would like to work and for whom.

If you are living in the Asia or Australasia region or plan to work in Asia or SE Asia then IALF Bali is the ideal location to undertake your TESOL (or TEFL) training. Regardless of where you are planning on working, the Trinity Cert Tesol will help prepare you for a future career in ESL anywhere in the world. As an easily recognizable international certificate, the Trinity Cert Tesol will open doors and provide you with a wealth of teaching opportunities worldwide.

Teaching English ......

  • ESL Focus A good site with solid information   http://www.eslfocus.com
  • Dave's English Teaching site =  Dave's ESL Cafe   http://www.eslcafe.com/ For ESL/EFL Students and Teachers from Around the World. Includes resources for bilingual educators - one of the big sites in teaching English. There are many others which you can find with a bit of internet searching. 
  • The Grand daddy of English teaching sites: http://www.tefl.com/
  • Vietnam 
ACET (Australian Center for Education and Traning): http://acet.edu.vn/   and there is also: VUS http://www.vus-etsc.edu.vn/  looking for ESL jobs: www.saigonesl.com

Getting the basic CELTA qualification from Language Schools in Saigon
Getting the basic TEFL qualification from Language Schools in Saigon
Jobs, Schools, forums, info....

As in all things in life, including you and me, there is a light and dark side:  here are links to sites that give a different perspective and look at the shadier side of English Teaching.