Cmadiam,
I'm assumeing that you run a hub and spoke type network. That you want these sites to access the internet through the HUB site. That your not running any routing protocols. Getting access to the remote sites may be as easy as configuring a static route into each of them pointing to the Hub site as their defalt route e.g
Ip route 0.0.0.0 0.0.0.0 (IP address of the up link hub site)
This depends on the hub site being able to see each of the remote sites and whatever firewall being able to reach the remote sites.
You could help a little by supplying some more detail, current configs would be excellent, (remove your passwords) a bit more description on what you want to achieve.
Hope that helps
Tony