Ethan
answered you on the bass traps outside of your room question...he said put them IN the room. If you put bass traps on the outside of the room they may absorb low frequencies coming from your room, but those are the frequencies that would have just passed through the walls anyway. You want to control the REFLECTIONS bouncing inside the room...not the stuff that's leaving (unless you're saying you want sound proofing help).
This has got some info on transmission loss of your walls. Not exactly what frequencies though.