Double inputs in sound?

[mxaaron]

I was wondering if there is a way for me to have both my guitar (that's hooked up to the input on the side of my macbook) and the built in mic to be on at the same time? On garageband, would it be possible for me to sing and play at the same time?

 

[UpQuark]

I was wondering if there is a way for me to have both my guitar (that's hooked up to the input on the side of my macbook) and the built in mic to be on at the same time? On garageband, would it be possible for me to sing and play at the same time?

To be clear, you want to audio input into garage band. One from your guitar and one from your mic.

http://www.podcastconsultant.net/2007/03/14/using-multiple-usb-audio-devices-in-garageband/

Take a look at that link, it might help you to get in the right direction.