Setting up an automated database like system for a website (see inside for details)

I just wanted suggestions from more experienced web developers on how you would set up a database for offers on a particular wine/champagne.

This system would allow me to create a new offer, choose 1 of several shops (in a previously entered list) in a drop down that has this offer running, a box for the name of the wine and then a price. This system would then tweet this, add this to a page, sorted by shop types and then be manually removed from a visible list by the admin when the offer has expired.

How would you program this kind of program as a web application. We currently use wordpress for our site, but we could create a separate page or a subdomain for this setup. I do of course realise this is very specific but I would be interested as to what I would need to learn (in terms of course on this site) and know as well as how I would start to go about this.

I am interested in creating a variety of similar systems, this is an example of one I though of that would solve a problem my dad has with his website. (he currently manually and very time-consumingly writes all of this information on a normal wordpress page on his site which is a very awkward system I would like to automate). Any information would be very helpful and I realise how odd this probably sounds.

Thanks in advance,