Welcome, coolhandluke!
To further clarify, Germany may move out of the sea zone in combat movement even if its ships end up in a friendly sea zone. Moving to avoid combat in this situation is considered a valid combat move.
Where to buy new kind of units? I want also a description of the unit like attack defense andfeatures
Check this site: http://www.historicalboardgaming.com
There are no rules for those extra units. You have to make them yourself. But then you can better go to the forum for house rules.