Does anyone have a clue how sites like ehow and infobarrel use adsense to track which user on their site gets the clicks and credits them accordingly? i want to host bloggers on my website but i want to take 25% of their earnings
they are doing adsense revenue sharing. some platforms have that options where you can offer revenue sharing option to your members. ehow, flixya, hubpages are giants and have their sites custom coded. if you use a platform that already have revenue sharing integrated then its easier. otherwise you have to custom code which doesn;t worth it for an individual site
That is going to be a coding question, not a Google Adsense question. Just make sure that you provide the code in a manner that doesn't fall outside of Google's TOS, otherwise you will unwittingly get all your site's contributors accounts banned. Probably wouldn't' make you a popular fellow.