Always check Free Public Records Search Directory to help lead you to courthouses etc. that make land records available online. In some cases they charge a (sometimes very large) fee but in other cases whole record sets have been digitized and may be viewed for free. Sometimes these images have indexes, sometimes not.
Choose your COUNTY AND STATE and pull down the Choose a Public Record Category to LAND RECORDS AND DEEDS
California, San Francisco County Records, 1824-1997 includes land records - at FamilySearch
California, San Mateo County Records, 1851-1991 includes land records - at FamilySearch
Georgia Headright and Bounty Land Records 1783-1909 at FamilySearch - there is a companion Headright & Bounty Plats collection at the Georgia Virtual Vault
Georgia: County Tax Digests from the Georgia Virtual Vault (give land details)
Georgia Colonial and Headright Plat Index 1735-1866 (no maps; just listings) from the Georgia Virtual Vault
Georgia: Chatham Co. Deed Books from the Georgia Virtual Vault
Georgia, Elbert County Records, 1790-2002 includes land records - at FamilySearch
Idaho, Bonneville County Records, 1867-2012 includes land records - at FamilySearch
Idaho, Butte County Records, 1882-1970
Idaho, Cassia County Records, 1879-1989
Idaho, Clark County Records, 1884-1998
Idaho, Elmore County Records, 1889-1972
Idaho, Gem County Records, 1877-1962
Idaho, Gooding County Records, 1879-1962
Idaho, Lemhi County Records, 1868-1964
Idaho, Lincoln County Records, 1886-1972
Idaho, Minidoka County Records, 1913-1961
Idaho, Teton County Records, 1900-1988
Idaho, Twin Falls County Records, 1906-1988
Illinois, DeKalb County Land Records, 1838-1927 at FamilySearch
Iowa, Poweshiek County Land Records, 1855-1934 at FamilySearch
MDLANDREC.NET From the Maryland State Archives has all patents and deeds for Maryland. You have to sign up for an account but they are beautifully done and amazing to work in. I am working on a help page for these. Once you understand how to use them they are fairly easy to navigate. Many of the earliest deeds are also indexed in the Maryland State Archives databases
Massachusetts, Land Records, 1620-1986 at FamilySearch
Minnesota, Clay County Land and Property Records, 1872-1947 at FamilySearch
Minnesota, Itasca County Land Records, 1872-1930 at FamilySearch
Minnesota, Roseau County Land Records, 1892-1930 at FamilySearch
Montana, Beaverhead County Records, 1862-2009
Montana, Big Horn County Records, 1884-2011
Montana, Cascade County Records, 1880-2009
Montana, Chouteau County Records,1876-2011
Montana, Flathead County Records, 1871-1981
Montana, Granite County Records, 1865-2009
Montana, Judith Basin County Records, 1887-2012
Montana, Lake County Records, 1857-2010
Montana, Meagher County Records, 1866-2012
Montana, Mineral County Obituaries, 1870-2010
Montana, Pondera County Records, 1910-2012
Montana, Rosebud County Records, 1878-2011
Montana, Sanders County Records, 1866-2010
Montana, Sweet Grass County Records, 1887-2011
Montana, Teton County Records, 1881-2012
Montana, Toole County Records, 1913-1960
Montana, Yellowstone County Records, 1881-2011
Nebraska, Broken Bow Homestead Records, 1890-1908
New York, Land Records, 1630-1975 at FamilySearch
North Carolina - Inventory of County Deed Records that have been digitized from the North Carolina Digital Collections/State Archives
Pennsylvania Land Records at the Pennsylvania State Archives is an extremely helpful list as many counties in PA have digitized their deeds. Some charge and some are free. Some have the images but no index. This is a good overview in one place.
South Carolina On-Line Records Index includes Plats for State Grants
Texas - Bexar County clerk site has digitized all their deeds. You have to register to search but it only takes moments!
Virginia Land Office Patents & Grants / Northern Neck Grants & Surveys 1692-1874
Washington County Land Records - Clark County
Washington County Land Records - Grays Harbor County
Washington County Land Records - King County
Washington County Land Records - Kitsap County
Washington County Land Records - Lewis County
Washington County Land Records - Mason County
Washington County Land Records - Pacific County
Washington County Land Records - Pierce County
Washington County Land Records - Thurston County
Washington County Land Records - Wahkiakum County
United States Bureau of Land Management Tract Books, 1820-1908 at FamilySearch
United States, Cancelled, Relinquished, or Rejected Land Entry Case Files, 1861-1925
United States Revolutionary War Pension and Bounty Land Warrant Applications, 1800-1900