Free parking. and correct, no bus transport to the parks, but there is to the resorts and that is free of course as well. and if you are staying at a resort, there is no parking charge for the parks, they will give you a voucher you put in your windshield that lets you park for free at all the parks. good luck finding a spot during peak times.
the last few times i have been it was crazy and took me almost 30 minutes to even find a spot. they desperately need more parking at the marketplace end. The parking lot is right out front of the DTD area. The Cirque tent is at one end and the shopping area where hte World of Disney is, is at the opposite end where there is less parking. Just follow the signs for Downtown disney and you can't miss it. I prefer to park near the marketplace side since that is where we spend most of our time.