Toronto - Calgary through the states

[sarita]

Hi,

I'm from the UK and hopefully want to plan a road trip from toronto to calgary across the top of the states. However, all the car rental companies I have checked have huge one way drop fees. Does anyone know of any that don't? I have also heard of something where people who are perhaps relocating want someone to drive their cars long distances, does anyone know anything about this? and any websites advertising this?
Finally I have researched some places of interest along the way although some with a slight detour such as Yellowstone and Blackhills, does any one have any good suggestions of must sees thats on route or not too far off route?

Thanks