One of the finest transportation infrastructures in the world makes everything easy.
The hardest part is getting to Japan. A round-trip flight will run you around $1K–$2K for a week-long stay. Once you pull the trigger, the itinerary can be simple and provide plenty of time to catch up on movies. Most flights to Hokkaido go through one of Tokyo’s massive airports, so make sure you book enough time to get from the busy international gates to the eerily quiet domestic terminal.
New Chitose Airport isn’t very close to downtown Sapporo, so it may be more convenient to take a bus to Rusutsu, Yubari, and other ski areas from the airport for a small fee. If you spend one night in Sapporo, however, you can get a free ride to Rusutsu on a bus that leaves from a stop near the train station every morning. The public transportation between the airport and Sapporo is clean and efficient.
If you’re comfortable driving on the left side of the road, in snow, and plan on skipping the complicated streets of Sapporo, then renting a car might be an option. Taxis are a better choice for most, and hotels will gladly organize one for you.