Welcome to the madhouse, Ympulse.
As for understanding the setting, the two books I would start off with is the 20th Anniversary Edition, as well as Augmentation, Unwired, Street Magic, and Arsenal. If you can't find them on DriveThruRPG or Amazon, just do a search through the internet, and you'll find copies. Two other books that really help in knowing the setting are Seattle 2072 and Sixth World Almanac.
Also, you might not be able to find them in print any more, but if you hunt the internet long enough, you'll be able to find some kind soul who will allow you to indefinitely borrow a PDF of their 3rd and earlier edition stuff. Going back and reading through some of the classic books like Universal Brotherhood - Missing Blood, Bug City, Renraku Arcology - Shutdown, Brainscan, System Failure, and more will give you a good handle on the world.
Now, as for where to play? If you've had no luck finding a group in real life, your best bet is to do online gaming. And now I'm going to throw some acronyms at you.
PBC - Play by Chat. Get on Google Talk, Skype, AIM, IRC or whatever messaging service you all have and go to town. The problem with this method is that things move very quickly, and you can get lost in the sea of information. Also, you have to manage schedules of people who may be in vastly different time zones. Still, it feels almost like being at the table with the group.
VT - Virtual Tabletop. Take PBC, and add pictures. Really, that's the only difference, though most virtual tabletops have other features like their own chatspace, an internal dice roller, map support, and so on.
PBEM - Play by E-Mail. The digital version of those old play by mail games, where you would get an actual letter from the DM, write out what you were going to do, send it in, and wait until the reply came back.
PBP - Play by Post. If you look at the roleplay section here, that is a fine example of play by post gaming. In general, I've found it to be a good middle ground between PBEM and PBC. Things move slower, but they don't depend on your schedules meshing like play by chat does.
If you're looking to get into a PBP group, throw up a request in the Looking For Game section. You can also hit places like Roleplay Online (
rpol.net) which offers free roleplaying options. If you do go over there, be sure to check in on the beginners forum, and people will be glad to help you get your bearings.