I got a job teaching english by just walking into a place that taught english classes (through old workbooks that the teachers just xeroxed and gave copies to students) and once they heard the way that I spoke, I had a job. No certificate, no TEFL course, no visa, no nada. Cash at the end of each week(you have to bargain for your terms).
Restaurant/bar work is pretty straight-forward. If they need the help, they´ll hire you. Bi lingual is a plus, but your natural english should help as many food establishments cater to tourists and an english speaking staff can make a place a good touri$t hang out.
I personally wouldn´t waste my time with a work visa, but then again, I´m just a guerilla tactics kind of guy