from a guy in the woods where you get the 2 farfech'd
Zen Headbutt is not a TM. It can be learned by leveling up, breeding, or by the Move Tutor.
top of the park
you get heracross or combees when you headbutt a tree
You cannot headbutt trees in any game except for Gold, Silver, Crystal, Heart Gold, and Soul Silver. You must teach a Pokemon TM 2 in GSC, or teach a Pokemon Headbutt from the Move Tutor in HGSS.
theres a guy in ixel forest and he will teach your Pokemon headbutt
a guy in the ilex forest
Use headbutt on a tree
Mostly any pokemon.
you go to the forest after you get the second badge and do the job for the guy then later in the forest you will find this guy doing a headbutt on a tree. talk to him and he will give you the TM for headbutt.
you go to Ilex forest and find a man in there and he will give you headbutt and teach it to you Pokemon and now you could headbutt a tree
Look in Viridian forest and headbutt trees.
You get headbutt in ilex forrest. There will be a man (who looks fat) that will give you the move headbutt. :):):)