Working with the City of New York, I helped draft Point, Click, Fire: An Undercover Investigation of Illegal Online Gun Sales.
The report argues that existing regulations fail to prevent felons and other prohibited purchasers from buying guns online, and it documents undercover gun-purchases that took place in Ohio even after the buyer stated that he couldn't pass a background check:
To our knowledge, this is the first report to document the enormous number of guns available for purchase on the internet, and the paucity of effective oversight governing these online sales.