Have you kicked it yet? I would try that first. If that doesn't work....
The only thing I can say is check the fluid. Thats about all the advise I can give you with my limited knowledge of automatics.
Hopefully somebody here understands the intricacies of the automatic, and can provide more help. Otherwise, I'm thinking rotten transmission shop.
If you decide to replace it (if it comes to that) you may consider putting a manual in, if you can drive one. There is much less to go wrong. Personal preference, though.
Oh, and thats what you get for buying a DSM.
Good luck with that, though.