Welcome! Open the text app, tap menu, tap settings, tap notification, select a new ringtone. Hope this is helpful.
Mike
Thank you, what's the texting app called? Because i don't have any text message sounds that i like on the ones that are programed on the text sounds.
I believe to use the method that Mike has described, the notification sound in question must be in a specific folder on your SD card. I want to say the folder is /sdcard/media/audio/notifications but i'm not sure if it's the same on the X as the Droid 1.
Don't mistakenly put them in /sdcard/media/audio/ringtones - if you do, they will only show up as phone ringtones.
To answer your question, I believe the app is called "Messaging"