Muck, ever been in the barony chair? The AF uses it to help guys in pilot training get over airsickness. You can make your own at home, and as long as you've got someone willing to spin you until you can't see straight (wives work well for this), you can be cured in no time.
Here's how it works. You get a spinning chair, sit down, and close your eyes. The first test is to have someone spin you at a constant rate until it doesn't feel like you're spinning anymore. Then they'll stop you and you open your eyes and almost fall over because all the fluid in your inner ear is messed up.
Next one, same setup, only this time turn your head to one side and lean forward. This time when you stop, try to raise your head upright and not fall over.
The last thing is just really something to do for fun, but pick something on the wall like a clock, and while you're spinning, keep it in sight as long as possible (keep turning your head so you can see it). When you stop and stare straight ahead, your eyeballs will still be moving back and forth rapidly.
All this might seem pretty silly, especially while you're doing it, but if you can get used to having the inner ear fluid spun and be comfortable with it, you'll do much better in the plane. Most of the time, when someone pukes, it's because of spatial disorientation (your body thinks you're doing one thing, your eyes are telling you you're doing something else).
Like the other guys have said, get a good solid crosscheck moving, with the majority of your focus being outside in the direction that you're heading, and occaisional glances inside at the ADI, HSI, altimeter and airspeed.
P.S. If you're still having trouble after a few more rides, email me and I can go talk to the Aerospace Physiology people, see if they can offer some more advanced stuff to help. They deal with this all the time.
