Yes, Gar' Udok will be seen in print and in an expanded format soon. We have retitled it so that it will roll off retailer's tongues a bit easier. It is now called Necromancer's Legacy. We can't wait for this to be out.
We also had some (from a company view) other sleepers that was nice for us. We suspected our Worldbook would do fairly well as we have a HROE fan base but the shocker titles are our non-d2o product, Giant Monster Rampage -2 fan sites and beginning to outsell our d20 products, which still sell high for the industry standard.
Our d20 sleeper hit has been Foul Locales: Urban Blight. It has outsold most of our other d20 product just on initial release and it is pickling up steam instead of going quickly off the shelf.
I think some sleepers outside our company have been Forgotten Kingdoms (Other World Creations) the Codex of Erde (Troll Lords Games) and Dragonstar (FFG- not sure if this was a sleeper hit or if I expected it). Ones I knew would hit were Arms And Armor (Bastion Press), Spy Craft (AEG), the Quint X (Mongoose). There are others but the list would get long.
I also think that Campaign Suite (Twin Rose) is finally getting the notice it deserves.