As far as I know blockchain.info and bitcointalk.org is work for bitcoin support freely,
And my question is ,who own it ,and who pay for it ?
Running a site like Blockchain is really expensive.
To find the owner of the site visit
WhoisXY.com Here they provide whois search tool which displays the details of a particular domain like domain registrant, domain owner information, contact details and so on.If that domain was registered under private registration then the registrant & some other details are hidden by proxy.