$7/hour is around R55/hour in South Africa, which is actually a great salary for most. But that figure is just for the top earners, I doubt most of the guides earn anywhere close to that.
Seems like it might be worth a shot to me. I'm a college student with free time on his hands and this might be both fun and profitable. Probably teach me a thing or two about information organization while I'm at it.
If you have time, you could check out sites like ehow. some ehow writers make more than $2k per month, but the difference there is you write once, and earn money every month (ehow shares its adsense revenue with its writers)