how to buy the xbox live gold for cheap with the halo reach item?

[pinkbits]

I'm currently xbox live gold subscribed, how do I buy the cheap deal, and add it to my account to receive the free item?

[Klevster]

I actually found this last night... It comes up on your Xbox once you've signed into Xbox live...

It cannot be found via their web interface, trust me I spent 30 minutes looking for it!

[pinkbits]

Where abouts on the xbox? I can't find it at all.

I've already got a current xbox live subscription, so I'm hoping it's not because of that.