Haven't played the game in a year, But I'm going back so lets see:
If its your first, then It can be a rather teep learning curve. Not as cushy as EQ but not as terrfying as UO. Also, I rarely find any 1337 C10N3r5 in game, they are all very mature.
The free expansions work like this: They are of coarse Free. You can either download them (I believe they are rather large, so only DL them if you have a high-speed line), or Order them, Or I received foundations in a Gaming magazine.
Definitly Midgard. Midgard is the Melee Realm, Hibernia is the Magickal Realm and Albion is both. Though, I find it more fun to play a Magickal race, melee is the best for begginers To learn.
Anymore tips? Just have fun, and ask any player if you need help.