U.S. Small Business Administration
Programs & services to help you start, grow, and succeed.
http://www.sba.gov

Business.gov, the official business link to the U.S. Government
This partnership, known as Business Gateway, is a Presidential E-government initiative that provides a single access point to government services and information to help the nation’s businesses with their operations.
http://www.business.gov/

Central Contractor Registration
The Central Contractor Registration Small Business site.
http://www.ccr.gov

U.S General Sevices Administration

The U.S. General Services Administration's site for information on becoming a GSA Schedule contractor, Governmentwide Acquisition Contracts (GWAC's) and Contractor Team Arrangements.

http://www.gsa.gov

AFCEA SIGNAL Source Book

Search the AFCEA Source Book - A great place to find partners or check out the competition.

http://www.afcea.org/sourcebook

AFCEA SIGNAL Source Book Special Report: How to Lose a Contract Proposal
AFCEA Small Business Committee Members, Government and Industry Experts Share Knowledge on Mistakes to Avoid in the Contract Bidding Process
http://www.afcea.org/signal/articles/anmviewer.asp?a=610&z=41

FedBizOpps
FedBizOpps.gov is the single government point-of-entry (GPE) for Federal government procurement opportunities over $25,000.
http://www.fedbizopps.gov/

Department of Homeland Security
Open for Business - Centralized information on how to do business with DHS.
http://www.dhs.gov/xopnbiz/

Acquisition Central
ACQUISITION CENTRAL is the web site for the federal acquisition community and the government's business partners. From this site you can access shared systems and tools to help you conduct business efficiently.
http://www.arnet.gov/

Federal Acquisition Network
Federal acquisition forecasts.
http://acquisition.gov/comp/procurement_forecasts/index.html

Virginia Procurement Technical Assistance Program
The Virginia statewide PTAP at George Mason University’s School of Public Policy Mason Enterprise Center is a non-profit program funded by the Defense Logistics Agency, George Mason University.
http://www.vaptap.org/

Fairfax County Economic Development Authority

The Fairfax County Economic Development Authority (FCEDA) promotes Fairfax County as a global business and technology center. The FCEDA provides a wide array of free and confidential services and information to assist expanding domestic and international companies and organizations.

http://www.FairfaxCountyEDA.org

Library of Congress' Guide to Federal Government Contracting

A general guide to Federal Contracting with many links to research sites.

http://www.loc.gov/rr/business/contracts/

Fedmarket.com

Some services on this site require a subscription but the link below goes to a useful free content page.

http://www.fedmarket.com/articles/index_freeResources.shtml