Throughout the game you will have the opportunity to tune into many radio stations via your Pip-Boy 3000.
These stations are available pretty much wherever you are in the Mojave Desert.
Mojave Music Radio
This station just has music, with no DJ.
Radio New Vegas
Based in New Vegas, and hosted by the smooth-voiced Mr New Vegas. Has music and news, and as your exploits grow, you might hear about them on the show.
Launch Music Station
Appears briefly at the end of the quest Come Fly With Me.
Black Mountain Radio
Appears when you are in the area of Black Mountain, but is unavailable when you stray far from it. Becomes static when you complete Crazy, Crazy, Crazy.
Camp Guardian Radio
A distress signal, starts a freeform quest.
NCR Emergency Radio
White Glove Society Radio Signal
Appears when you enter the Ultra-Luxe casino, but is inaccessible. Future DLC, perhaps.
Sierra Madre Broadcast
Appears once Dead Money has been installed. Advertises the Sierra Madre casino, which jumpstarts the DLC.