Add invoice number to web order form

Existing web based order form. Ideally want the following modifications made : 1. When user presses submit button, invoice number is to be displayed (can this be auto generated in the format 2011/xxx ??? is it possible to auto generate???) 2. Generated email (on submit function) to include invoice number (modify existing on submit function) 3. User to have the ability to change the year on the invoice number for each subsequent year 4. Details from order form (if possible) to be downloadable to an access database. In your submission, please quote on items 1-3. Item 4 is not essential, but optional. Please provide a secondary quote for this work.