Rodney, like JohnK was saying, you generally want an equilateral triangle--the distance between the speakers should be about the distance you sit from them. There is no hard/fast rule for toe in. Start experimenting.
Soundstage and imaging are somewhat synonymous, as far as I know. Soundstage is the ability of the speakers to create a "stage" in front of you, a sort of 3D representation of the music. Imaging, I think, refers to the ability to locate sounds and instruments within that soundstage.
In a recent thread, I found that moving my speakers 3" further apart and my seating position 5" back had a profound effect on the sound. Sometimes small changes make a big difference. Try all sorts of things to familiarize yourself to how the speakers should sound--toe them out, toe them in, stand up and listen, walk around the room, all the while paying attention to what happens to the sound.
