I am wondering how I would be able to connect my front end sitting on my desktop to my access backend sitting on my companies sql server? What types of addresses would I need to be able to connect? How responsive is it via the internet?
Well, with a VPN connected your server doesn't need to be publicly exposed. The user would be "on the network" at that point, so your linked tables should still connect. Performance would likely suffer, as Albert discusses. If you have SQL Server available, I'd use that as the back end. Properly designed, that can still perform well in a WAN environment.