One of the better ways to grill a turkey, is to do it in halves. I've tried
this, with the cut side facing down on a metal baking pan, and it seem's to work
out best - keeping more juices from escaping.

Another trick I've learned is to inject (literally, using a syringe), using a
combination of your favorite spices, and oils. I usually inject it several
times as much of the marinade will "bleed" back out again. I've found that
letting the turkey set in your refridgerator for at least 1 day, gives it more
time to marinate.

You'll probably have to baste the turkey a few times with a brush during
cooking, but having the cut portion of it facing downwards also seems to help a
little in drawing up additional marinade. The meat comes in direct contact with
it, as you inject it too.

If anyone has any other neat tricks, let us know!