Re: Pullup Routine?
Like others have said, lots of pullups. I do 5 in every circuit set I do. Mix in chin ups, and other styles of pull ups and you'll be fine.
I also like the pyramid plan in circuit fashion (starting at 10 go down, exercises I do are: 50-70lb kettlebell swings, pushups, pullup/chin up, push ups, tricep bench dips, rest. then repeat).
Good luck!