Help with recording through line-in on Macbook

Hi, I've searched all over the internet for an answer to this question, but I haven't found anything straightforward, so here I am.

I'm using a new Macbook (my first one), which apparently has no line-in jack. I've heard that the headphone jack can be used as a line-in, is this true? I'm trying to record audio from my device that I have connected with the appropriate cord, but I get nothing when I press record in Audacity other than the audio recorded from the built-in mic.

So, is it possible for me to record this way, or do I need to purchase something else to do any audio recording? Is there any configuring (in System Preferences or whatever) that I need to do to get the device recognized? Also, how do I mute or disable the built-in mic?

Many thanks to anyone who can help me.

You can select which method of input recording to use by going to System Preferences, Sound. Click on the "Input" tab and select "Line In" as your choice. (Highlight it.)

That should shut off the built in microphone and allow you to record from the input jack. Try it with Audacity, it should work.

Regards.

Oh... I tried going there before and I thought selecting my device wasn't an option. I obviously overlooked it. Thanks. It's finally working.