Nationwide has gathered other articles and quality sites related to telephone services:
Reference guide to all things VOIP
Definition of Internet telephony
How Voice Over IP Works from Howstuffworks.com
What is VoIP? from SearchNetworking.com
Guide to Telephone Services from University of Florida
Telcompare.com - Comparison site of long distance rates, voip, local phone service, international calling, international callback, calling cards, cell phones, dial around, conference calling, toll-free services, dsl, internet services and satellite tv.
International Long Distance and T1 lines - Use the calculator at USATalkCheap.com to compare and find the cheapest long distance carriers in your area.
Cheap and Free ISP.com - Directory of cheap dial-up isps. Also cheap T1, DSL and Satellite ISPs, cheap long distance providers and much more.
Comsearch.net - ComSearch is a directory of business and service Web sites, manually compiled by professional editors.