Recording on new macbook pro

Hello all, Ive searched multiple sites, and have tried all the ways of figuring this out, but its led me here, with hopes you will be able to help. My wife bought me a macbook pro for my DJ gigs I do every week, and I have always wanted to record my mixes for people who are not able to hear them. I use a Numark mixdeck, and have an RCA to 1/8th cord that i was able to use on my old toshiba laptop to record (only in mono). I tried the same thing with the macbook, but found there was no external mic port to use, so i tried the headphone port, only to find it wont recognize its an input not output. I looked on sites to find a fix where I would be able to change the option of output/input in the sound preferences, however, that does not exsist on my model. So now is my dilemma. Does apple make some kind of cord (thunderbolt perhaps?) that will help see the external input? I was hoping not to buy an external soundcard that would use a USB port to record. Hope you guys can help!