Folks who do this kind of research usually know each other, since there are so few... and at one time or another we bump into each other doing original research.
The earliest Adams County records are bundled with York County until 1800, when Adams County was established.
For Land Records - copy and past the following address into your browser and hit "enter" - http://www.phmc.state.pa.us/bah/dam/rg/di/r17-88WarrantRegisters/YorkPages/r17-88YorkPageInterface.htm
Here are some other folks who have done fine work that you won't find elsewhere.
ADAMS COUNTY, PA LAND RECORDS:
The Manor of Maske - It's History and Individual Properties, Adams County Historical Society, Gettysburg, PA, Charles H. Glatfelter and Arthur Weaner, 1992, paperback, 74 pages. $10.60; $11.85 by mail.
This volume details the history of the 43,500 acre manor, dating from 1741, and the acquisition summaries of some 333 original settlers.
The Manor of Maske connected-draft survey map, a companion to the above book, 36 by 48 inches, Charles H. Glatfelter and Arthur Weaner. $21.20 on-site; $22.50 by mail in PA; $24.25 outside of PA.
Hankey, Joan R., comp. Guide to Warrants and Patents in Present York and Adams Counties, Pennsylvania, (1996), $12.72, $14.00 by mail.
Books and map are available from the Adams County Historical Society, Box 4325, Gettysburg, PA 17325. Inquire about current pricing.
GO TO THE ADAMS COUNTY HISTORICAL SOCIETY PAGE for a full list of their books in print and pricing. Civil War era volumes, Battle of Gettysburg, and ghost stories, too.
MARYLAND LAND RECORDS
Olde Map Shop,6790 White Rock Road, Sykesville, MD 21784; George Horvath - proprietor, (410) 526-4878; deals with the following original researched and published Maryland land records for:
Old Hamstead (Cox's Town)
Ward's Chapel Area, along Liberty Road, west of Randalstown
Baltimore / Carroll County Area
Freedom to Winfield Areas, along Liberty Road
Ruxton and Riderwood Areas, near Towson
Green Spring Valley Area
Finksburg to Westminster, along Old Westminster Road
Pikesville Area - from Hookstown to Greenspring Valley
Randallstown Area, along Liberty Road at Old Court Road
Owings Mills Area - along Old Reisterstown Road and St. Thomas Church
Union Bridge Area - south to John Gillis' Land
Winfield (Old Baltimore county to Delaware Falls in Howard County
Elkridge to Ellicott's Upper Mills Catonsvlle
Rayville to the Maryland Line along the York Roads.
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