While it is OK to be careful beforehand, being too hesitant may not take you anywhere. There are some very clear criteria to follow and to select employers abroad. If you followed these guidelines, you would significantly diminish any risk. The first thing would be to learn more about the employer in addition to the job description. Get involved with any, but when you find during the application process that there is something fishy or that rings your alarm bells, withdraw and cut off the contact!

@ turnoi: you are right on the money there. I have become more wary since the last traumatic incident. to be honest it has kind of put me off teaching english.

Cheers for the support though!