It use to be 6 weeks but I think where I live it is 6 months...I'm not sure just ask where u want to have it done at they all will have differant rules.
my family does it between 2-3 months old. usually any place that sells earrings does it. in my mall there's a Piercing Pagoda, and they do it. im sure if you look online they'll be places in your area ! (:
earliest is 2 months after they get those 2 month shots...