The Internet Archive—Archive.org Books, periodicals, sound clips, and images digitized by a consortium of libraries and made available to the public. You can download these items.
Google Books—www.Books.google.com Books and periodicals digitized by Google, primarily before 1922, are available in full text access. You can search the whole database or search within a publication. You can download books or save them to your library with a Google account.
Hathi Trust—http://www.hathitrust.org/ Books and periodicals digitized by Google with the cooperation of several large public and university libraries. This database is provided by these libraries for the public to access. Hathitrust contains many of the items that Google has, but it is organized in a much more user-friendly way. It is organized into a catalog so that it is searchable by title, author and keyword and offers a nice interface to read online, but not available to download. Publications before 1922 only available to public due to copyright restrictions.
Project Gutenberg—www.gutenberg.org – Project Gutenberg offers over 40,000 free e-books: choose among free epub books, free kindle books; download them or read them online.
Library of Congress American Memory Nineteenth Century in Print Project, in conjunction with Cornell University and the University of Michigan–http://memory.loc.gov/ammem/ndlpcoop/moahtml/ncphome.html
Fulton History— http://fultonhistory.com/Fulton.html. Search this site for the Rhinebeck Gazette, Pine Plains Herald, Poughkeepsie Eagle, etc. This site is difficult to use but there is a lot of valuable information available. It is worth taking the time to figure it out. Index of all publications, not in alphabetical order: http://fultonhistory.com/my%20photo%20albums/All%20Newspapers/index.html
HRVH (Hudson River Valley Heritage) Newspaper Collection— http://news.hrvh.org/ Kingston Freeman and many other regional newspapers
Library of Congress Chronicling America— http://chroniclingamerica.loc.gov/ , local and regional newspapers from around the country.
New York Times— http://0-search.proquest.com.gigcat.midhudson.org/accountid=35824 Only available to those with Mid-Hudson Library System Cards, you will be asked for your barcode and password.
Historical Newspapers— http://0-hngraphical.proquest.com.gigcat.midhudson.org/ Only available to those with Mid-Hudson Library System Cards, you will be asked for your barcode and password.
Digital NYS Archives — http://www.archives.nysed.gov/d/
National Union Manuscript Collection — http://www.loc.gov/coll/nucmc/oclcsearch.html