still dont know what you lack so i'm going to assume everything.
Couch to 5k - C25K Running Program
that should get you started. jump in on the week that you think you are capable of doing.
yes to LSD work, since doing that it helps stamina across the board, helps recovery time too.
the general consensus on this thread is dont get in shape to train, train to get in shape. so go and jump into the 12 rnd class