Dennis
Greece and Turkey are surprisingly easy - no problems at all.
However, make sure you book the Italy-Greece crossing in advance (you'll probably be OK in October. If you don't like camping, invest in the cabin. (I went from Ancona).
Costs were approx £90 for the bike and deck space (i.e. camping) v. £240 for a cabin to yourself, or £140 for a dorm. Try a search for "Superfast Ferries" and you'll get all the pricing etc. etc.
Turkish/Greek border is a piece of cake, though can be long winded if you don't know where you're going. Don't hang around in the queues though, drive straight though, park up the bike and then walk everywhere. You need to go to the big office first for a visa (£10), get it stamped in the first "box", then get a form from the the second "box" stamped etc., then pay 20 euros or so at the third "box" (you need to show your papers at this box). Then at the final exit, you show the various print outs etc. and you're on your way. There were hundred of cars/people in the queues, but no one really has any sense of orderly queuing, so just get stuck in!!!
There are some great roads in Greece. If you're down south, we can meet up some time and I'll recommend some places. Turkish roads aren't in the same condition as the Greek roads, but fun all the same. There are alot more lorries at low speed, so you'lll be practising your filtering and overtaking manouvres for sure!!
I'm in North London, so if you fancy meeting up before hand, give me a shout. I've got the maps etc. which will help to talk through the route and options.
L