Using Asterisk to trace spoofed calls

I am being harassed by some prank caller that is spoofing his/her number neither T-Mobile nor the police can do anything about it. I have been told from one of my friends that if I set up an Asterisk server, I can accomplish the tracing of the prank caller. I am hardly knowledgeable in terms of networking, so a lot of what they told me was filled with jargon I couldn’t really understand. But first things first, I downloaded Asterisk 1.5.0 and was finally able to install it (had issues with partitioning… In the end I just had Asterisk hog the entire HDD space).

Now that I have finished installing Asterisk, I have no clue what to do next. I suppose the next step is to go downstairs and connect my laptop via a CAT5 cable as our wireless network is fairly slow and unstable. I am more used to using a GUI, and apparently Asterisk doesn’t come with one. I’m a debian user, so I’m unfamiliar with how exactly CentOS works as well. I did some searching, and trixbox is supposedly user-friendly, so I’m downloading it at an agonizing speed of 10kbps. But yes, what should I do next? Do I need a PBX card for what I’m trying to accomplish?

EDIT: By the way, will I have to open any ports for the server? I have limited administrative permissions because of my father who is very uncomfortable with opening ports.

I have no idea how you can trace calls tha’t come from the phone line, never heard more bullsh… you just simple can’t get more info from a call the the callerid.
the only thing you can do is thank your friend for the time you spend trying to do something you just can’t