I have also contacted Bill and the prices are very good. Thank you for the information.
However, they don't offer on-track insurance, so we are still shopping around. Here is another one you can try. They offer coverage for racecars on-track, off-track, storage, and transportation, and their rates are very reasonable. They also offer coverage for trailers and contents. I believe there is a limit for the 1/4 mile E.T., so this company may not work for everyone.
http://www.racecarinsurance.net/