As above. Some planets you won't even be able to enter because they have shields and you need permission to enter.
Most cities also are just for production or financial purposes (i.e. for the faction to make money), whilst most of their members go and do stuff like building, security, etc. You will rarely find anyone in a city but NPC's, creatures and vehicles.
However this doesn't stop you Role-Playing that you landed in X city and have a great time with other Role-Players :D
What Hal said is very important. IRC channel #swc-members is unfortunately littered with trolls. Mind you, there are alot of friendly rooms and people who want to talk :)
Come to #swc-ic, there'll be alot of people there willing to help about how to Roleplay, and teach you, like myself :). Faction IRC channel's that you are in are very good and are also fantastic to get to know your fellow comrades, as well as learn more in a friendly environment.
I have a cafe called #happycaf you can also come into and I'm there when I'm on the IRC which is quite often :)
Other than IRC, forums are very good to be around. Try your hand at a competition in the Gambling Hut, or come to some RP! Either way there are alot of ways to do so! Feel free to DM me if you need anything at all, and I'm certain that probably goes for most of us who have replied.