very top left hand of the map
Until the Broken Steel DLC comes out I don't think that you can join an organization.
The brotherhood outcast will come after you... but don't worry it's not much of a problem as along as you have some laser rifles or assault rifles... WORD of advice. If you are going to kill the outcast... make sure you raid fort independence to get some powerful weapons like the gastling laser.. or PLASMA rifles. ( this only applies the fallout 3 in dc and not fallout 3 new Vegas)
There are about 50 at Fort Independence.
you will find loads of ammo and a medical power armor
If you want an abounded one its called abounded car fort" not very big but i think it is cool and a non abounded one the citadel brotherhood of steel fort.
Joining enables you to download bigger mods so if you like mods, Yes.
Sometimes maybe 5 or 6 mercs will respawn at Fort Bannister be cause some of them were "on missions".
No that's horrible, kill them all and set free the slaves. Plus if you side with them the people at independence hall won't like you.(that might not be the name but the place where you get the quest to find a picture of Abraham Lincoln's head.
Occasionally Fallout: New Vegas will freeze, but not as frequently as Fallout 3.
There is no such place in fallout 3.
fallout 3 psp??????