That quote is totally out of date and incorrect. But if you have been here 5 years in any type of legal residency and now have permanent residency you can buy a firearm. If you want to carry it you will need more paperwork to get a permit. I have a CWP but I have yet to figure out how to conceal a gun in the light clothing we wear hear. Presently I use a fanny pack but it is rather awkward.
There are at least a couple of ranges that offer training and testing for the permit, they also help you with all the paperwork. I can't find the reference at the moment but any gun shop will direct you.