I had originally booked with rD for Marathon weekend, and gotten a pretty good deal. But then, I found an agency with group rates, and whoo boy, I saved 30% on my car insurance room rate by switching to one of them.
Naming them is difficult on here because of who owns these forums, but do a search on Google for "January cheer package disney" (without the quotes) and it'll show up. It's not meant for cheerleading, but cheering on the runners. It's some odd wording on the agency's part.
Another search for "Disney agency exclusive deals" (also without the quotes) will get you another company, but also with really good rates.
Another great discount is to rent DVC points