I found an article at WoWInsider with “two tricks that will allow you to do the majority of your traveling as a ghost.”
1. If you die on one continent and then spirit rez in the other (yes, you can ride boats and zepplins as a ghost!), you’ll be allowed to rez right where you want to.
2. If you run as a ghost to wherever you wish, disconnect, reconnect, and then try to spirit rez, you’ll be allowed to.
