I'm partial to the fiddle with it till it sounds best approach. for a starting point ,though:
1. try to get the tweeters at about ear height from your listening position
2. keep them out from back and side walls, I like to givr mine 3-4 ft. space in all directions, then move them in and out till they sound best.
3. try to place them in an equalaterial triangle to your listening position.then move them around until a center image is in the center.
4. start with the speakers toed in to face your listening position, then nudge them out until you loose the center image,then nudge them back until you regain it.
5. if you get a good center image with the speakers facing directly toward the back wall, try moving them a little further apart until the image is lost, then toe them in until it's regained( or closer togeather if the image is week even when the speakers face your listening position).
This is easiest if you have a helper. What your after is the best soundstage you can get.
+1 however I would add that fiddling with placement can have dramatic changes to the sound and of course it is completely speaker/room dependent. Lucky for you it is a pretty intuitive process.
Differences in sound in my setup have been impact, tone, soundstage, and presence.
As far as stands go, don't sweat them too much. Any stand is going to improve things some tweeter height and positioning will matter more. Stands will help by giving your positioning more flexibility.
My dealer carries Sanus primarily and I think they do a fine job.
Sam
