Can someone explain to me where I would find the proper post is to find where D clone will spawn and how I would find a game in the same area where people are selling Sojs?

Now it's not based on ip in d2r, it's just based on regions. That means it can either be spawned on Americas, Europe or asia.
You can check the approx soj count by typing /uberdiablo

To have him spawn you have to be o the server where sojs are sold in hell game before he spawn. That's all

^ What he said. Also, you need to be on the same core (Softcore vs Hardcore) where SOJs are being sold.

Example, if dclone spawns on hardcore americas, you won't get dclone on softcore americas.