You can change your hometown once but only once. To do this, go to Cor Noth into the Hall of Genealogy (across from the Adv. Hall) and go and read the books. There's one book for every hometown (Tos, Barloque, Jasper, Marion, CorNoth)
Say aloud the last line in the book of whatever you want your hometown to be. Choose wisely because it's permanent.