Database Project

I need someone that is familiar with appending of data. I need a database system built that will run appends. If you dont know what email appending, postal appending or appending of data is then i would guess this isnt the project for you. If you are familiar i would love to hear what you can do for me. I would need to have this solution produced so that i can run both postal and email appends to my clients file. We are going to need to run millions of records at a time, so that needs to be taken into account. You can get an overview of what appending is at my site www.dhinteractive.net. let me know if you have any questions about this.