I seem to be having a similar issue. I'm new to forums so bear with me if I unwittingly break any protocols. I've downloaded ringtones from myxer and can play the files in the media player, but when I hold down on the song from a playlist the option to set it as a ring tone is not there. Just purchased the phone on Saturday and loaded 2.1 the same day. Any help is greatly appreciated.
Figured this out on my own. Hope I didn't waste anyone's time.