Connect 2008 black MacBook to 2013 MBA via Thunderbolt / Firewire?
What you need is a FireWire 800, according to this post from an Apple discussion board. Monoprice is a great, online retailer that has cables for a really low price. Take a look at the results that I have linked you. Remember, you need the 9 pin to 9 pin cable if you want to connect two Macbook Pro's together.