How to i report fraud on the web and to whom I should report?

be more specific, was money taken from your justification? is it stolen items on sale? what manner of fraud?

who you report too depends on what it is...

example: you carry an email that looks like its from paypal, but you assume it may not be. You can forward that email to: spoof(a)paypal.com

if you get one from wall of america that looks fake, you convey to: abuse(a)bankofamerica.com

Answers:
To the hosting company or the offending site's ISP and the law enforcement authorities within the country where the fraudulent site is hosted.

You should report it to the Internet Crime Complaint Center. Also known as IC3.

This is a collective partnership between the FBI and National White Collar Crime Center.

Better business bureau or www.ripoffreport.com