Getting access to a rocket launcher in Borderlands 2.

I am in a mission where I need to use a rocket launcher but I don’t know where to find one. Any help would be appreciated. Thanks!
Answer #1
gibbed’s save editor ?
find the code for a gun online and cheat it
Answer #2
you can look here for trainers. they don’t list cheats for this game, but some other site may have them if the trainer don’t have what you want. http://www.gamecopyworld.com/
Answer #3
You do not need a trainer.
Just kill enemies, one will drop a rocket launcher, or check boxes or buy one at a shop.