Well, personally, I'd say don't bother with PeerGuardian.
It's completely useless in my opinion, here's why:

Firstly, let's assume that PG's protection is *perfect* (a big assumption) - ie, that it has every single law enforcement agency's IP and can block it.  Problem is, it can't protect you from a lot of your P2P activities.  For torrents, this is how it works:

Your PC sends request to tracker --»  Tracker broadcasts your IP to everyone  «-- law enforcement agency grabs list of IPs from tracker

As you can see, they won't even target your machine - your IP is being broadcast by the tracker, so PeerGuardian can't do poo poo to protect you, since it's the tracker which dobs you in (has nothing to do with your computer).  Once they have your IP, a simple lookup will reveal your ISP (again, has nothing to do with your computer, the IP is owned by the ISP).

Then secondly, obviously it's impossible for it to have a list of all agencies, in fact, I wonder how they'd even get close to a reasonable list...  If I could easily bypass it, why would an agency have an issues with it?