Google phone owners sometimes have bad luck when it comes to accessories, compared to say the Motorola Droid, iPhone or Blackberry. It’s easy to find good cases and docking stations for those devices.
I finally found a hard shell case for the Nexus S that isn’t terrible. The one at Best Buy is a terrible kludge and I have yet to read anything of good value about it. Google phones tend to have a lag time of 2-4 months for any accessories to show up. At $10 shipped, this isn’t a bad buy, either. Also comes in some patterned models, but jet black is probably the best way to go with this one.
Avoid the super low end cases, the silicone gel ones. There’s a reason why you don’t see anyone but 16 year old girls using the gel cases – they’re terrible. Practically everyone I know had a hard shell case for their 2g/3g iPhone, and they lasted a long, long time.