I ma currently running a Mac OSX computer on a school network.  I am
attempting to use a P2P program (either Limewire or BitTorrent) 
However it appears that the ports ahve all been blocked.  How do I get
around the blocked ports in order to use the software and download to
my heart's content?

As an ordinary user on a network you can't unblock blocked ports.  You
would need administrator privileges to do that.  You can try to change
port number used by the software by rummaging around the options menu
for that particular software, but more than likely the network
administrator would have also disallowed any programs from opening new
ports, in which case you're SOL.