Demetrio Tupac Yupanqui (as far as I'm aware not a member of AW) has put an Quechua course online at this adres:

yachaykuna

The language in which the course is given is Spanish, but I'm sure that even without knowledge of Spanish, it can be fun.

BTW This is part of Quechua Network, a lovely site with loads of information of the present day Tawantinsuyu...and it's got English pages too. Adress?

quechuanetwork.org