What are the best places to visit in Fallout 3 for Xbox360?

I have been struggling with this game for some reason. I keep finding myself trapped in areas with no ammo and barely any health. Any tips for me? I don’t have any schematics and can’t seem to find them. I blew up Megaton and have a place in Tenpenny Towers, and I can’t even find Moira to buy the schematics off her for the Rock-it launcher.

I also already have Paradise Falls as a place to hang out.