How to insulate a concrete block shed - material / method
The most efficient (highest R-value for the least cost) is batt insulation. 

For the walls, You say, "solid block wall", so I presume it's not hollow blocks. So, installing rigid insulation boards on the exterior and then covering it with a moisture barrier (building paper, peel-and-stick membrane, etc.) and then covering it with, as you say, "timber tongue n groove" will give you both the insulation you need and the waterproofing you need. This can be done using wood stripping installed the opposite direction you're going to install the "timber tongue n groove". (Placing the insulation on the exterior will help with the size of the spaces too.) The thickness of the rigid insulation depends on the thickness of the stripping and how much you can afford...generally R-21 is recommended. The stripping should be easy to install if the blocks are solid and not hollow. 

For the ceiling, providing a pitched roof with R-38 batt insulation is recommended for your location. Be sure to vent the attic to prevent condensation and ruining the insulation. 

For the floor, we don't worry so much about concrete slabs on grade. The cost is too great compared to the benefit of adding perimeter insulation.