Monster iPhone – Everything iPhone

i want to add new ringtones to my iphone. also can i use songs in my iphone as ringtones?

if you have a windows pc,

http://www.efksoft.com/products/iphoneringtonemaker/index.htm

if you have an intel mac,

http://www.modmyiphone.com/wiki/index.php/IFuntastic_easy_iPhone_ringtone_installation