I mentioned this site to Dickhead yesterday. It is one of several online digital libraries open to the public and "housed" at the University of Michigan. A number of very old historical texts from the 19th century are included that deal with the development and exploration of the west. This may prove to be a very good resource for us as historians. Check it out.
http://quod.lib.umich.edu/m/moa/Then there is this one (I don't care what Rush sez about Congress, you gotta dig their library):
http://memory.loc.gov/ammem/index.htmlTheir railroad maps are especially COOL:
http://memory.loc.gov/ammem/gmdhtml/rrhtml/rrhome.htmlAs is "The Nineteenth Century in Print":
http://memory.loc.gov/ammem/ndlpcoop/moahtml/mnchome.html