I wouldn't expect to see Kliper of Buran any time soon. Actually, the Buran Shuttle no longer exists-it was destroyed when its hanger collapsed. I think Buran's sister ships still exist but they were never assembled, so I'm assuming they are sitting in pieces somewhere.
As far as Kliper goes, they have designs on the drawing board. Unfortunately, they need the Russian government to come up with 10 billion roubles to fund the program (and we all know how these programs run way over-budget, they'll probably need 15-20 to get it actually flying). So, I doubt we will see either of them in the near future. Right now, the plan is to have Kliper flying by 2010, so I would expect to see it make it's maiden flight in 2015 or so (knowning how these things tend to turn out). The fact is there really isn't a rush for it. The current version of the Soyuz (TMA) made its first flight about 2 years ago-so its still pretty new (although based on old systems).
To sum it up, I don't see any replacement for the shuttle (or the Soyuz for that matter) before the next 10 years. We need it to finish ISS (which is supposed to happen by 2010-and probably won't, I honestly don't think it will ever be completed) and that isn't possible without the shuttle. Plus, we aren't going to abonden the most reliable spacecraft that has ever been built because of a few problems. Wait and see, Discovery will make the return to flight mission-in 2005.
