I have found they have just about anything I want. I use the "Crank Ring" from the movie Crank...Chev Chelos' phone uses it throughout the first movie. It's just a plain ring tone that fades away...I like it.
I'm assuming you have the same capabilities as I do w/ the Storm... I just load my iTunes onto my phone via DM and can choose my own songs for my ringtone.
Since you can only export the songs edited in Audacity in .wav format, you will need to convert them to .mp3 format in order to make them compatible on your BlackBerry. There are many programs out there that can do this, but you need to search a lot to find a free one. I recommend Xilisoft Audio converter.