I think you could probably get berserk from the bloodsouls that are around galbadia garden's old hangout. They cast it a lot anyways-_-

My favorite way to kill marlboros is to smack them with demi about 17 times, then have rinoa devour them for the spirit boost eventually I'll make a dent in her spr stat then I can have someone else devour. You can draw demi from them, so you don't have to worry about running out or having to equip the Magic command.

If you don't have berserk and confuse junctioned, do NOT junction against sleep. Having a character confused and berseked but wide awake and poisoned is *NOT* a good thing.