Was in iguazu 2 weeks ago - see my account in answer to a iguazu query in south America thread. Fantastic experience - do it if you can. We flew into IGU on LAN from Lima then on GOL to Rio ( with touchdown in Curitiba) for around 100 dollars, booked on their web site. They were very good. There was a big variation in flight prices so check options carefully - I think ours was cheap because of the touchdown and also because it went into santos dumont rather than GIG.