Design Website/program to assign umpires

Design a website/program for assigning umpires I'm looking to have a website/program designed to automate some of the tasks involved with the assignment of umpires. some of the key tasks: umpires to log into a site and input availability ability to input the games ability to select number of umpires per game ability to notify umpire of assignments ability for umpires to accept/reject assignment ability to create payroll by leagues ability to manage multiple leagues concerns - things unsure of: - should this be a SAAS offering hosted by us - should this be an app offering - downloaded and hosted by user - can this be integrated into a website, have it's own website, or should it all be hosted from one main site? - should this be built on php, asp, or java platform Here is a list of similar sites/programs: [login to view URL]~neelam/abet/SITEVISIT/758Project/Blue%20Elephant%20Referee%20Scheduler%20%28E%29/WWW/[login to view URL] open source software