[1.5.1] Modding Help

[cja711]

Im looking for some help, Im making a mod where I need a book, when right-clicked, to be placed on the ground and then spawns 1 mob that i still need to code, then the mob can be right clicked to open a gui. Please help with whatever you can. Thanks

[Draco18s]

Im looking for some help, Im making a mod where I need a book, when right-clicked, to be placed on the ground

 

That will require an entity of some kind.  And probably a model to go with it.

 

and then spawns 1 mob that i still need to code, then the mob can be right clicked to open a gui. Please help with whatever you can. Thanks

 

And that requires things I don't even know about (haven't touched mob or GUI code yet).