I agree with a lot of the suggestions given.
One thing I would add, is perhaps to practice the behavior during non-event times. Randomly drive to places with the dog crated, practice the ritual of leaving, coming, going, etc. Sometimes covering the crate helps, depends on the dog. You can also try giving the dog special items when crating in the car/at an event - like a stuffed kong - so he has something to do in the kennel. Reserve that special treat for your practice of this behavior. But, if you give him/her something to do, you can only give it contingent upon the desired behavior: quiet.
Never release the dog from the kennel for whining/barking. Even if you get only a millisecond of quiet, mark and reward it, then release. Practice entering and exiting the crate from the vehicle alot, again during non-event times.
Is the dog crated at any other times? I try to start new/foster dogs off with crate type games. I made a vid of what I do with them, if they have never been crated before or have negative association with the crate: www.youtube.com/pitzncatz
There's a vid called Crate Training/Building Drive, in it I am training a 14 week old pit pup that I fostered for awhile. I try to build enthusiasm for the crate. I haven't seen Susan Garrett's crate games, but I'm told that the ideas are similar. I have seen her lecture and think she's great, so I'm sure that her methods would be fun and effective.
I regret not having worked more with Mojo on crate behavior as a youngster. he has great crate behavior at home, but not at events. He doesn't compete in anything, but is often along for the ride, or has to be crated if I take him to class. He's definitely gotten better over the years, but I regret not working on it earlier/not really knowing to do so as I didn't know as much about training then. Rumble crates nicely at events, and I think it is in part b/c he's a quiet guy anyway, but he's had the most rehearsal of it out of all my dogs. The one time he will make noise in a crate is if we are at flyball, and he sees me run Mojo. He doesn't seem to care if I run other people's dogs, but if I run Mojo at our practices, he squeals.
Barking is a hard behavior. I used to see alot of my flyball teammates struggle with it. It always bothered me to see some people squirt their dogs with water when they barked. It has to suck to be confined and squirted at. And honestly, it takes just as much physical effort to go to the kennel and randomly reward quiet behavior with praise and a treat, or release!