Possible Clues:

• Neighbour of Michigan
• Smallesr of the 5 great lakes
• Where baseball was first played in Canada
• Neighbor of New York
• Canadian province between Manitoba and Quebec
• Province by four Great Lakes
• London location
• Its postal codes start with K, L, M, N and P - but, oddly, not O
• Ottawa's home
• Site of Waterloo and London