You will find information about your Karns and Mearkle family on many of these sites. Take a look.

Mower Family Web Site (provided by the Mower Family Association; many Mowers intermarried with Karns family members)
Genealogy Site of Jean (Karns) Ladd (space provided to Jean by Family Treemaker)
The Bedford County, PA Web Site
(provided by Rootsweb)
USGenweb Archives (provided by Rootsweb)
GenServ (a subscription service providing many family databases)
GNIS (maps provided by the Geological Survey service of the federal government)
World Family Tree (a subscriber service to a large collection of family databases)
Family Treemaker Family Finder (a subscription service)
World Tree (a service provided by Ancestry)
Anywho (a people finding site)

Links checked okay on 24 Jan 2011.