If you never read Vernor Vinge (except for his essay on the Technological Singularity), what would be the best book to start?
If you're looking for something more germane to present concerns, Rainbows End is about a near future where people's interaction with the world is mediated by augmented reality and various forces are fighting over access to information.
And since I haven't seen it mentioned here yet, Marooned In Realtime is also really good.
But if you're looking for a single book, then you won't go wrong with A Fire Upon The Deep.
Across Real Time is also great and shorter.