look up youtubeplay. it lets u download youtube videos straight to ur phone. itll even let u extract the mp3 straight from the vid. i recommend this in conjunction with vito ringtone editor. u can get a free trial for 14 days, or buy it for $7(or if u want a discount, type in "twentyoff" in the promo code box when buying). vito is extremely easy to use and lets u make ur own ringtones. ive made a few myself.
hope this helps,
Ryan