Hi, I have the newest iBook 12". I noticed it only has audio out. What is the cheapest way I can get my guitar and amp connected to my iBook. I've seen some devices before, but they seem too expensive. With the one device i've seen, it hooks your guitar up to the iBook, but when you record in Garageband, you only can hear what you play during playback. So I need something that would also be able to hook up to my amp so I can hear while i'm playing. Bear with me if I was a little hard to understand. Thanks.