The classic modern canard right here (Rutan Long-EZ):
Photo © Darren Wilson
In another tech/ops thread I'm involved in, another poster mentioned that the canard mounting point is a "busy" area of the plane's structure. I could see how putting an engine in there would just make things a mess.
It seems in the case of the Beech Starship, they *could* have used a tractor configuration, although the engine nacelles would have to have been longer to keep the props from hitting the swept leading edge of the wing. Then the aircraft would have benefitted from induced lift due to the prop wash. Then again, it is a product of Burt Rutan's mind.
Photo © Jaysen F. Snow - Midwest Tail Chasers
I'd bring up the Piaggio Advanti, but there seems to be considerable debate as to whether or not it's really a canard