Autofire web application

i would like to know how can i create an application that periodically perform a background task in my web server?
this is because i need the application to auto-retrieve data of another website(others ppl's website) and automatically update the data into a database in the server(autorun for mayb every hour...etc).and i can't use scheduled tasks in my server to do this.
so, how do i start to build the application?
hope you all can help bcoz this is the first time i build a web application and i have no idea how to start it.
thanx in advance.