WiFi Legal Stuff

Does anyone know what the legal output limit is for a WiFi device?

Or where I can find more information on the subject?

in america they answer to the FCC's requirements, here we answer to the MED

http://www.med.govt.nz/rsm/planning/srd/di...cussion-05.html

(for true wifi you're looking at the 2.4GHz spectrum, though 5.3 and 5.8 will be of interest too as that covers a few other technologies covered by the colloquial use of "wifi")