Noob here. Just a week into this, so pardon my hard ignorance. I'm learning as fast as I can.
I had half my coins on Poloniex (now I see what a mistake that was). If I withdraw, and then do the split using the guide here, will I get the BCH?
No. The BCH are on poloniex's wallet.
Can someone help me out with something?
I had my bitcoins at a site before and I waited for BCash to come into existence after which I was planning to redeem my Bitcoins to my wallet which I did.
How may I now claim BCash? Am I eligible to get them or was it a perk for those who had their bitcoins at exchanges already?
The BCH are on the "site" you're talking about. Either they will give you the corresponding BCH, or you're screwed.