As far as netbooks goes, I have a bias towards ASUS (as I've had excellent experiences with their customer service for Motherboards and Notebooks).
I like the Asus EeePC 1005HA although the Acer Aspire One D250 is also good, but I have some reservations with Acer's build quality in the past.
I'm not sure your price range, so I picked less than $350 USD. Having a price range might also change your needs from a netbook to a high end notebook.
What sort of software do you use from your netbook (MS Dynamics, SAP, Office Software, etc.)
Also have you considered getting a 3G card or would you prefer a laptop with built in 3G?
The netbooks I selected both have over 9 hours of battery life (although that's a liberal estimate, I think it would still be plenty for long road trips).