I had the same issue last night when I tried to purchase ebooks from Mobipocket. It binned several books I had selected on the grounds that the books are not available in MY country (UK) so I couldn't purchase them !!
I found a great website
www.diesel-ebooks.com which discounts many books, checkout is hassle free and great selection of ebooks and prices to boo. I will no longer purchase direct from Mobipocket, prices higher, Vat for EU buyers.
Hope this helps.