So I saw a video on Youtube posted by Apple. The guy in the video plugs his 1/4'' cable to an adaptor, which connects to his GarageBand on his iMac. I'm wondering where I can get such adaptor and connect my electric guitar to my MacBook.

Yes but there are a ton of reasons why it doesn't work well. Try posting in the 'Recordings Forum' and those guys can help you figure it out a bit better.
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Unless its electronic drums.

There's a sticky in the recordings forum dedicated to providing advice about interfaces. Go there.
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You want to give your female a male adapter so she can exchange data with other females?

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Last edited by DeathByDestroyr at Nov 21, 2012,
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