It is possible that Stephen is away on vacation at this time. In Europe, it is not uncommon for businesses to simply 'close for vacation', rather than making arrangements to stay open 52 weeks a year, as is the practice in North America.
I am not sure where you will be entering Europe, however, if you are entering via Germany, just go to any ADAC office (the German automobile club - there have offices in every city), and buy your foreign moto insurance there. It costs €22 per month. You have to buy it in person, you cannot buy it via mail. What Stephen does is simply to go the ADAC office and buy it there for you, then he posts it to you.
Another alternative - perhaps better if you will be travelling outside of the EC countries - is to contact Gail Goodman at Motorcycle Express (http://www.motorcycleexpress.com
) and buy insurance from her. You will have to fax her copies of your documents, etc., and she will then courier the insurance document (the 'green card') to you. The insurance from Gail is considerably more expensive than the ADAC insurance, but: It covers everywhere from Iceland to Israel, with the sole exception of Iraq - heck, even Iran is covered. The ADAC insurance only covers the EC countries plus Switzerland. From the description you gave of your planned route, I think you would be better served getting the insurance from Gail.
I bought a policy from ADAC a few months ago to cover my wandering around Western Europe (F, CH, D, I), but when I made my trip to Ukraine and Romania a few weeks ago, I called Gail to get a month's coverage from her.
Gail is a good person to deal with, I have been buying European insurance from her company for about 4 years now. It's not cheap, and they do require a lot of documentation to be completed, but they are fast and efficient once they have all the documents, and if you have a claim (I had one once), the post-accident service is absolutely first class - no hassles at all.