You can find a lot of great toys at Petsmart. If you don't have a store near you, you can order on line.
Here are a few of my cats (Ellie 2 years old, Smokey 6 months old) favorite toys:http://www.petsmart.com/global/produ...=1131981975225http://www.petsmart.com/global/produ...=1131982082497
I also bought these from Petsmart (but they do not have them online) it is called Petstages cheese chase cat toy, and catnip feather pair. You can purchase them from the online store I found the pics from.http://www.cattoys.com/cheesechasetoy.htmlhttp://www.cattoys.com/catnipfeather.html
That is great you are going to get her spayed!
As far as the tree goes, I am not sure if she will mess with it. I adopted Ellie this past March and brought home Smokey in July. This is the first Christmas with both of them. I have decided not to put up my 7ft Christmas tree, instead I am putting up a 4 1/2 tree with non breakable ornaments. I wish you and your little ones a safe and happy Christmas.