We (as a group) really need more information – so I’ll start with some assumptions and questions.
1) Do both sites have High-Speed Internet access? By this, I mean DSL, Cable Modem, Satellite, T-1, Frame Relay, etc.
2) Do both sites have firewalls (As opposed to proxy servers) for the Internet access?
If the answer to both of these is “Yes”, then you should be able to set up a static VPN tunnel between the two.
Since I don’t know if you have those connections, and especially since you haven’t specified a brand of firewall, it’s difficult to be more specific.
Most brands of firewalls (NOT routers, which may ACT as a firewall, but still lack some of the features) like Sonic Wall, Cisco Pix, and others can be set up this way.
Please reply with more information, including the following:
* Type of Internet connection at each end, including speed
* Type of firewall/router/proxy at each end
* Geographical distance between the two points (miles)
* Working budget (approximately)