Where can I buy a Cata CD Key for Gold?

[Warcraftwoman]

I remember seeing a site selling Cata keys for gold, among other things. I tried a google search and came up hopeless. I am a bit uneasy trading my gold for a key but I want to peruse some sites that might sell them.

I am on Crushridge US Horde and want to get a CD key for my second account (Dropping $40 on Wrath hurt my sanity and I want to avoid another blow to the wallet).

Can anyone suggest a site you have used to purchase CD keys and preferable known to have Cata keys?

Thanks

[Anaidni]

I haven't personally used gold4key, but they seem to have mostly positive reviews, and show that you can buy a cata key on their website.