since google say they only want one ad showing up per search so for instance if I search newbie cash machine I would only see one ad showing the site directly the others might be review or something are you allowed to buy a domain name and then redirect it to the affiliate site containing your link thanks
That thread is dealing with double serving, he is talking about redirects. For tracking purposes you can redirect as long as the display url matches the end result url, (after the redirection). However blatant redirects that are not for tracking purposes and where the display url does not match the end destination are not allowed. Mind you it's hit or miss if they catch you. One way around that is to make a landing page, get them to click a link on that page then make the link your affiliate link. More steps and you may lose the clicker but that's the chances you take.
look under Affiliate policy https://adwords.google.com/select/guidelines.html states they dont allow redirects just build a 1 page review site or pre-sell the item and pass them on to the affiliate site, you will need other pages though to give your site quality
This is why most of the ppl get stuck with adwords as the rules are updating all the time that it is hard to keep updated.