Players interested in registering and participating in NFL mock drafts before their own fantasy football drafts can do so for free at ESPN.com and Yahoo.com. The registration requires signing up with a valid email address and disclosure of some personal information.
Most mock drafts involve participating with real human players around the world. Some sites, however, allow players to try multiple mock drafts against computer artificial intelligence. Sites like FantasyPros.com offer both free and paid registrations to use this type of service. The free version does not require registration of any kind, but is limited to basic scoring models and league types. The paid version allows many more league customization options and does not cap the number of mock drafts a user may run.