I recently had a several things robbed from my place, and one of the things of course, was a PS3. Now, I'm not sure if the their has reformated the system, and I'm not sure if I can redownload all my stuff and play it again on another system. Can I do that? Or do I have to get a new PSN account? (Which will suck a huge NUT if I do)
Yes. You can download all of your PSN games and DLC to two specific PS3s at a time, so you still should have one left. Once every six months you can clear all of the activations from your PSN account, so if you ever need a second replacement PS3 someday (or if you already have two or more PS3s activated), you can deactivate your account from the one that was stolen.
gkpama00 answered your question nicely. I'd just like to offer a suggestion. Change your password on the new PS3 especially if you have the stolen one set to auto log-in.