A few comments:
1) There is a dedicated Ringtones, Themes and Wallpapers forum
2) This has been asked (and answered) at least 100 times
3) Seriously - search is your friend.
Take a look in the Ringtones forum and read the Sticky Threads. This has been answered so many times before.
Answer (too tired) - no; you use the browser to download them from a website. No USB...