Alannah (my paladin, Alliance): Came through as reinforcement when Khadgar brought troops through into the Garrison. She serves as an attachment to the Garrison in Shadowmoon Valley, but largely has been left to do her own thing given her status as a paladin. She has traveled some in Shadowmoon Valley, done quite a bit of fighting against the Pale. She can often be found in one of the Draenei settlements around Shadowmoon, favoring Elodor as a resting place when she can escape combat.
Yalayna (my monk, Alliance): It's not quite clear how she ended up on Draenor, though she likely followed some group of night elves through. She also is largely left to her own devices on Draenor, and is currently hanging out at the night elf outpost near to the garrison, though she will likely make her way to the Spires of Arak and lend her aid to Southport.
Lukar: It can be assumed Lukar would have been right at the front, leading a charge through the Dark Portal, once more picking up his weapons in defense of a world on the brink of destruction. Little can be said for what happened once through the portal though. Some may have seen a warrior in Lukar's usual green armor, wielding Mooncleaver, laying into Iron Horde left and right. Others might have seen a similarly-armored orc fleeing the destruction of the Portal with the rest. All that can be said for sure is that Lukar is now in Frostfire Ridge, helping to secure the future of the Frostwolf clan.
Purveyor of Alternate Moral Choices