is it hard to mount one? i am new and think it will be fun

Tanning their fur is easy...

I may be wrong but, I think he wanted a little more info than that!!
If this is the first time youy have mounted anything, you may want to go to Van Dyke's taxidermy supply website.
They have a kit just for starters, and you can learn a little more of what is involved.

My thought are... practice with squirrels first. A rabbit has VERY thin skin. I would practice on a few squirrels first. Squirrels are easy to get and are pretty tough. I agree about Van Dykes kit.

Like what was said above, squirrel's are a lot easier to mount. I've mounted one rabbit and let me tell you, their skin is like that of wet tissue paper.