I'm not talk about their locations, but making meshes that have them all...
WoWhead has a list of all the innkeepers, not that hard to convert into a xml.
As said above acutally getting to the inn is the hard part - none of the large profiles currently have a path to all the inn keepers (unlike flight masters which is how eTrain operates). As such it isn't really plausable unless you want to walk around and make meshes of every city so that the bot can navigate to the inn keeper.
It doesn't have xyz coords so it isn't that easy - you can't just convert them.
you can always try some emu-dbs and hope that they are as blizzlike as possible, they will have xy and z . I just don't know how accurate it will be.It doesn't have xyz coords so it isn't that easy - you can't just convert them.