The easiest way probably to do it is if your digital camera has a video feature just record. Don't put the microphone too close, probably 5 or 6 feet away, because it'll overwhelm the little mic on the camera. Just connect the camera to the computer and go to YouTube and find and upload the file from the camera. It's pretty simple.

Also, I have a sound clip of my stock exhaust on YouTube if anyone needs to compare.