There's a small little app in the marketplace called "Tone Picker" (like 40k and free) that lets you use other media apps to select ringtones and other audio clips, say for alarms, or sms notifications. Combine that with a file manager like Astro and you can then put your audio anywhere on the card, in any folder and you can use Tone Picker to let you point to it. Works very well.
I did this so that I didn't have to put the same sounds in Ringtones, Alarms and notifications as the built in picker only can look at one place at a time it seems. (Alarms looks at alarms, ringtone at ringtone folder, etc...)