While I have no idea about shipping costs from California to Denmark, I can offer a few suggestion. First off I would send an email to Orion and ask them for advice on shipping. I am sure they can help you, or can advice you regarding what companies here in the USA that can. Orion does not ship outside the USA and Canada, but you could contract another firm for such, or even a private individual over here who would help you persue a study of astronomy.
The list of accessories for any telescope can stretch around the Earth! But the primary things you will want include good eyepieces. While Orion supplies 2 good Plossls - a 10mm and 25mm - I would suggest also suggest a 17mm and a 12.5mm, as well as a good quality multi-coated Barlow lens for doubling your magnification without reducing eye relief. Hunt around in Europe for these, as importing may prove costly. Good Plossls can be found over here for around $30 and up. A good Barlow runs about $40. Of course, you could easily spend 2 or 3 times this amount if you wish to get top of the line TeleVue EP's and Barlow. At some point you may wish to consider using a 2 inch eyepiece for amazing, wide angle views of starfields and extended nebulae. For your amusement check out an excellent 2 inch EP at:
At $95US it sure is more affordable than a 31mm TeleVue for $620!
If you are planning on doing a lot of planetary observing, you can't go wrong with a set of colour filters for bringing out the details in things like Jupiter's belts and Saturn's rings. Filters are a available individualy and in sets of 4. Here they cost around $10 - $12 each.
I would also look into Orion's latest offering of their computerized "IntelliScope" controller. I have their older SkyWizard didgital setting-circles on my Orion f4 equatorial reflector, and it really helps for finding deep sky objects. Armed with that and their offer of a free copy of The Sky Version 5 Level 2, you will have around 19 million objects in your database of things you can locate. Though not all would be visible in an 8 inch scope. Or an 18 inch one either!
And I am glad you are going for the 8 inch Dob. There is this large leap between a 6 and an 8 inch scope, with the 8 inch really opening up your abilities to get a good look at deep sky objects and do serious astronomy. An 8 inch telescope can keep you entertained and enlightened for a lifetime!