Most manufacturers have rough-in dimensions available on their websites.
For regular 2-piece toilets, we use, 6" to the left of center line of flange, and 6" up the wall. If you have a large baseboard or tile base cove, then you might go a touch higher, say 8".
For a lavatory sink (sink set in a cabinet), 10" down from finished counter top height and 4" left and 4" right of drain center for your hot and cold. (see this for a better explanation)
If you're using a pedestal lav, then you really need the rough-in from the manufacturer, but you can still use the 10" down from sink top (flood rim) and 4" off center left and right for the water. The drain is the one that really needs to be at the proper height.
For shower-only valves, we set them centered on 48" off finished shower floor and centered on the shower wall. The outlet is set @ 6'6" off of finished floor unless you have someone over 6' tall in the home, then we might set @ 7'.