Anyone know how to use iTunes? I cant figure out how to download the ringtones I got
 

I have an iphone and went on to itunes on my computer and bought some ringtones.
I see them all sitting there in my "Downloads" folder, but theres no want to download it on to my iphone.
I keep click Sync, but they dont download.
In my library theres no folder for ringtones.

ahhhhh so frustrating.
this cant be this complicated.
how do I get the ringtones and app on my iphone please?