Speak to local contractors or nursery people about who does that work - you don't want to have some eager beaver make a mess with those things, or end up with someone's broken tractor on your property.

An excavator is really the best machine. It doubles up as a very versatile crane. You will need it for moving soil, digging ponds etc anyway. A small one weighing 2.5 tons will easily lift a 0.5 ton rock.
You will need a lot of good rope to hitch the rock to the scoop since the scoop cannot grip all shapes. It is easy to hitch to the teeth of the scoop.

It sounds so Exciting!! I think that how ever you do it, (the 2 posts above sound like super advice) you are wise to do the rocks /hardscape first, and resist the temptation to leap ahead to some part of the project you could do later yourself, just because its so gratifying to see some piece of a long anticipated project come to life. I have the perfect private seperate corner in the back of my garden for a Japanese garden, but Ive made it very difficult by not planning stuff (like getting the rocks first). Now the garden in front of the area is so intensly planted that it would be a big diaster to bring in the rocks Id have liked to have had. So... A) Good luck, and B) stick to your plan. Oh, and lets see some pictures when you are underway.

Several years ago I placed all of the rocks in my garden with a boom truck. I used a 10 ton crane mounted on a flatbed truck with a 60' boom. It was rented from a rentsal yard. I could not get any equipment into the garden area, so I was able to sit on the edge of it with the crane and place rocks. My heaviest rock was about 3000lbs. It is best to rig rocks with a chain. You can basket the in multiple directions and the after placing the rock, you can pull the chainout with the crane.

Be prepared to spend some time placing your rocks. I placed 7 rocks and it took me about 6 hours to do it with the holes already dug. I found this to be a very spiritual experience. The depth of the rocks and the strata lines are very important. You must look at them from many angles untilk you are satisfied with them.