Item should be added to Hira Snowdawn
NPC: 31238 in Dalaran, although on many servers I've found it is added at all Northrend starter town on either the mount vendor or riding trainer.
you can buy this item only if your character is level 77 or higher, its working as intended (its a heirloom, you have to mail it from one of your other characters)
Not available from NPC's (currently on a level 70 character with several 80's on account.)
Tome of Cold Weather Flight http://old.wowhead.com/item=49177
Item should be added to Hira Snowdawn
NPC: 31238 in Dalaran, although on many servers I've found it is added at all Northrend starter town on either the mount vendor or riding trainer.