[Centos] Help with moving from Fedora to Centos

[cburnat at burnat.com (chris burnat)]

I have just installed centos 4 on a spare box - working great.  Until 
now, I have been using Fedora Core3.  I wish to move all of my mail, 
address book and bookmarks created in Thunderbird and Firefox from the 
Fedora system to the new Centos system.  Would someone kindly point me 
in the right direction, I am relatively new at linux.  Many thanks for 
any assistance.  christian