So you want some cool ringtones but the music you listen to isn't supported by Tmobile website... or the I'm too cheap to pay 1$ for a ringtone because I blew 200$ on my phone.
Step 1. Get Audacity. http://audacity.sourceforge.net/
Step 2. Find a file named Lame_enc.dll This is the mp3 encoder needed for audacity to export files as mp3 files.
Step 3. Find something worth making a ringtone out of. Audacity has an excellent ability to record anything you can hear through your speakers. I instead just loaded the program.
then open the mp3 file I wanted to use
In this case I choose a file I recorded while I listened to it for the sole purpose of turning it into a ringtone.
takes a sec to import it. Then Play the song to ensure it is what you want. Also note the time marks for when you want the ringtone to start and when you want it to end.