There's not really a right or wrong answer to this question.
It all generally depends on one's ability to socialize and preference when makin' acquaintances. Sometimes friendship can be acquired through role-play (a good place to start here would be in Fluorite Plains where a variety of role-plays are held), sometimes it can be gained through a simple conversation (dependin' on yer comfort zone, ye' can find friendly faces in every public map here though if ye' like locations with a lot goin' on, I'd take a peek in Bonfire Island, Fluorite Plains, or Ficho Tunnels while if ye' prefer more quiet places to just have a casual chat every now and then, I'd look in maps such as South Pole, Temple of Dreams, Cape of Distant Worlds, etc), then some players actually find a majority of friendly faces here on the forums.
Again, it depends on the person. In this case, ye'.