If you have web browsing in your phone go to 3gforfree.com it's completely free it's been around since 97 or so and completely free no catches like those that are on tv now a days.
if you want to be creative and make your own ringtones, i use www.mobile17.com
this is what i do
since my phone only plays midis, i go to vgmusic to find a midi that i like, then you just put send it to mobile17, and they will send your ringtone via text message