We have recently finished a component that will allow the site owner to upload Excel files that create new records for them. The customer is ShellStockReview.comand they use this new component to update their Stock Profiles. (Unfortunatly, To see this component in action, you will need to be a member of their website community.)
The original component ( Content Uploader - free version) was designed to allow admins to upload Excel files to create articles. We modified their component to upload specific data into new tables and then use this data in their own views. The component comes complete with a back-end area to manage the uploaded records and the ability to add new records, as well as added front-end views to see the uploaded data.