I would like to display to my users, similar to how Groupon does it, their current geo location when they come to my page.
I have found an option to do this with HTML5, but that is not compatible with all the browsers I want to support.
What options are there for providing this functionality?
All geo location solutions I have seen are tied to a server side code, which takes the users IP address and looks it up in one of the available IP <-> geographic location mapping databases.
The first step in this process would be to get access to a service like Quova and then integrate it into your system.
Once you know their location, you could write it to a cookie along with their IP address. Load the cookie when they come to the site and compare it to their IP address. If the two differ, perform a new geo location lookup.