The shop by the airport is indeed still open and doing business (yep they still sell bikes and souvenirs).
The Al Wakra store is easy to get to, at the airport lights (heading to the airport from the D ring) turn right and keep going, you will reach Al Wakra withing 10-15 minutes dependant on traffic and how heavy your right foot is.
On the left hand side of the second roundabout (the one with fountain and clam shaped thing) you will find the new HD shop, also a Kawasaki shop.

You're born, you take s**t. You get out in the world, you take more s**t. You climb a little higher, you take less s**t. Till one day you're up in the rarefied atmosphere and you've forgotten what s**t even looks like. Welcome to the layer cake son.