Well you've given a broad description of what you need. Where do you start?
You start by planning the application. First, decide exactly what you want it to do. Be very particular in this stage because the development process will go much quicker and easier if you don't change your goals during the development.
Next, once you've written down all the goals and mapped out the basics of the program, note all the database requirements (tables, fields, etc) I see you have already started that.
Once all the planning is done, create your database tables and start the coding. I usually start with the backend stuff (authentication scripts, class definitions and function libraries) to support the application. Once the functionality starts to come together, I then start to write the interface component of the application (the forms and such that make things happen).
After that's all done, you debug and review, debug and review, etc..until everything matches the goals you set in the beginning.
Finally, you present it to the client and he changes his mind on a lot of things and you have to go back and make changes and it's a real pain in the ass. But you'll find out all about that once you get there.
