So, I found a pretty cheap Camaro for sale, but they said it needs a "tranny linkage." I've Google'd it for a bit but never really came up with what exactly it is, or how you would replace one. Any advice?

Any help?

I think your refering to the TV cable (throtle valve ). It goes from under the hood to the tranny basically makes sure the tran shift points are set properly. If this is what you are refering to it is a $25 part and is not difficult to install. It needs to be set properly as well see my thread regarding the TV cable there is pics in there of the cable. Even if you had it installed at a shop I wouldn't expect it to be too expensive. Probabbly charge you an hours labor and parts.