Suffix Titles are earned with quests, Killing mobs, and /claim rewards. Your Suffix to your name, I.E. your last name is availible to chage/add at level 20.
For example:
Sentry Phalong of Povar
My prefix is "Sentry". Earned with an AA line, STA for crusaders.
Name: Phalong
Suffix "of Povar" is a server name in EQ1 that I played on before beta testing EQ2 and then playing EQ2. I thought that sever names where only availible to beta testers, but Ive seen some people who didnt beta test with it, so im not sure what the requirements are now.