basically, latin america is a super place to go to because its so cheap.
the best places to go are chile, argentina, peru, and im not sure about the rest.
if you go to latin america, you will have very little trouble getting a teaching/language assistant job if you're fluent in spanish, and the cost of living is very cheap. the only real expense would be flights, around £300 each way. i wouldn't recommend going through an organisation because quite frankly, if your spanish is good enough, you dont need to pay the extra costs involved.
it's up 2 u really, maybe you would feel more secure with an organisation.
let me know when you're going. i MIGHT go to chile summer 2007.
regards,
ryry