Original Message: Reputation Notes from TEF's Guide to Enroth
Here's a near-verbatim copy/paste from my old website. (Even if I included the style sheet, it would still look awful, so apologies to your eyes in advance.)
Reputation in the Land of Enroth
Caution: Here There Be Spoilers
Everything you always wanted to know about reputation, and then some. Nearly all of the information can be figured out on your own (paying just a little bit of extra attention).
tl;dr version (set to, "50 Ways to Leave Your Lover")