Im sorry to inform you,. but the 9th edition has been sold out for quite some time now. There's an outside chance that you might be able to pick up a used copy, but thats doubtful.

You will be able to pick up a copy of the 8th edition.

The 10th edition will be out in 3 1/2 long months. My information is that it will be out at the end of May.

I would expect the new 10th edition will have quite a few changes from the 9th, because of new discoveries over the past three years.