There are so called ressource areas, I know of three of them, Poitain, Lacheish Plains and the Purple Lotus Swamps. All those Areas are with a relatively low monster population and in all of those areas Guild Cities can be build furthermore, in all of those areas there is at least one NPC city inhabited by Tradeskill trainers who give the quests nessecairy to learn a trade skill.
BUT the ressource nodes can be found in nearly every area (exceptions are for e.g. inside of cities or dungeons)