From first-hand experience, B2B sellers do not get this information today. They typically get "signals" like "Company X is searching for product category Y" or

From first-hand experience, B2B sellers do not get this information today. They typically get "signals" like "Company X is searching for product category Y" or "Company X is visiting your web site". And "Company X's CIO is John Smith - here's his phone number". But nobody that I've seen claims to offer individual names of web site visitors.