Here's the thing:

I have a MacBook in my room and I have a cable that connects my guitar to the recording input in my Mac. However, I want to have a full recording interface thingie so that I can record my vocals and my piano on it, too. (I use GarageBand, but I bought Logic Express although I've never gone around to learning/using it.)

So basically, I'm looking for a recording interface thing (if that's what you call it) that would let me record my guitar/bass, vocals, and piano on it. I'm guessing the set up would be like this:

MIDI on Piano ---> Recording Interface
Guitar ---> Recording Interface
Bass ---> Recording Interface
End of mic cable ---> Recording Interface
Recording Interface ---> MacBook's line-in

Also, would it be possible for me so that if I were to record instruments simultaneously, like Guitar and Vocals at the same time, for them to be two separate tracks?

Thanks for any help.
You could get a mixing board. Like a Behringer, theyre cheap and good. Everything can go into that and then out to the built in input. That's how I do it.

Theoretically though, if you have the chord to attach your guitar to the computer, that takes care of the guitar and bass going in. If you have a MIDI keyboard they have USB outputs, so just get a USB cable to connect it. You could always just record the vocals through the built in mic. It's not that bad if you get close enough to it.

And no, you can't record two things at once on to seperate tracks.
I'm guessing you don't have a Mac or Garageband??

Because if you have a track you can add effects to it, like a guitar track you can add distortion and wah to it, vocals they have a ton of presets, and for keyboards, too. That's why I want to be able to record each track separately. (In Garageband)

And I'm not a noobie at this either - I've worked with DAW's before and have a ton of equipment. I'm not going to use some built-in mic when I have $200 condensers lying around.

I'm not trying to be mean - I was just looking for a better answer. Sorry.
buy an audio interface that connects via usb or firewire with at least two mic/line input and with a midi i/o built onto it or you can buy a midi keyboard with usb. One channel you can record guitar and the other channel you can record bass/vocals. you can find any audio interface at any local music store or online music store. also i have a mac and gargage band is horrible. if you bought logic express you should really learn how to use it.
I am a fan of MOTU gear. You could look into products by them as well as
I was once heavily prominent on these forums from 2004-2007, let's see how long I can stay now that I'm back.