Just a very basic description on the server spec:
http://www.eqpvp.com/index.php/topic,4.0.html
You can join either Qeynos, Freeport, Rivervale or Halas. This option is available in Nexus, visiting an emissary to bazaar (formerly shadowrest) is the easiest way (East Commons tunnel, Qeynos Hills shack near North Qeynos, Everfrost ent to halas, outside oggok in innothule, butcherblock docks, etc.).
Kingdom players have a home town so they can fortify through guard upgrades.
Otherwise you can just join Bandits which is the free for all team (either hitting 30 and auto-setting PVP or going to a Priest of Discord in a non-kingdom city).