I remember a long time ago you used to be allowed to change your home city, can you still do that? It seems that many cities have registration offices for becoming a citizen.
Changing your home city?
Yep. The offices are still around. The cost becomes exponentially greater, however, as you level up. Seiluna had a heck of a time changing her citizenship from VM to Shas.
Can I change my town for example if I not a drow to Xymerria?
no.
Well, how do you do it? is it a RP thing or is it coded?
You can change to certain cities based on align and race. It is coded. And the cost does get greater as you level.
A pinn'd character will usually cost over 1 million gold in some cases to change.
Except in extremely excellent RP situations coupled with an extremely good application, your choices are limited to what they were at creation. Some exceptional few have been able to get other choices with stellar RP, and of course, a price that's not simply gold.