It takes a lot more energy (electricity) to produce hydrogen, than to just run a vehicle off of electricity directly. Creating hydrogen is very inefficient, and if you buy a hydrogen powered car, then you have limited choices as to how that hydrogen was made (via coal fired plants, or solar panels, etc..) But if you bought an electric car, you could charge that vehicle up any way you wanted to. Get some solar panels on the roof of your house, and boom its almost free (during the summer) to charge your car. Or plug it into a parking lot's flood light stand, like where you work and charge it for free.
Or, if your Electric company has a green plan, sign up for that.