Entry Page for Multi-Store Site

I am looking to have an entry page ( see attached ) on my multi-store site. The entry page is where the visitor would enter the delivery address and the system would return a list of stores (pizza shops) that would deliver to that address. At that point the site-visitor would choose a pizza shop and continue with the order process

You can use the landing page mod in the extensions store or just code a page calling it like index.html and set htaccess to load that page first.

My site is similar to Eat24.com where the "physical" delivery address must be verified to see whether or not that address is contained within a restaurants delivery area ( also known as a geo-fenced area or polygon)