Here are some links we find to be helpful:
MARYLAND GOVERNMENT AND INDUSTRY
Maryland Land Title Association
Maryland Department of Assets and Taxation (SDAT)
Chicago Title Insurance Company (Fidelity/Ticor/Commonwealth)
Maryland State Bar Association
Judicial Case Search
State withholding for Non-Maryland Sellers
Washinton Suburban Sanitary Commission (WSSC)
VIRGINIA GOVERNMENT AND INDUSTRY
Virginia Land Title Association
Virginia Department of Taxation
Chicago Title Insurance Company (Fidelity/Ticor/Commonwealth)
Virginia State Bar Association
Virginia State Corporation Commission
DC GOVERNMENT AND INDUSTRY
DC Land Title Association
Chicago Title Insurance Company (Fidelity/Ticor/Commonwealth)
DC Bar Association
Real Property Assessment Database
District of Columbia web site
DC Water and Sewer
FEDERAL LINKS
Internal Revenue Service
US Department of Housing and Urban Development (HUD)
Public Access to Court Electronic Records (PACER)
1031 Exchange
FIRPTA withholding for Foreign Sellers
OTHER USEFUL LINKS
Zillow.com – estimate the value of a property
Martindale.com – find a lawyer
Wikipedia – Description of Title Insurance