The typical method of producing those posters (and money) is known as intaglio printing; this process used etched copper or zinc plates. This allowed for much finer lines and longer print runs (since the plates lasted longer) than woodcut printing. The downside to this method was that it was an "all or nothing" type of thing - ink was either applied or it wasn't (think of a rubber stamp). Because of this, if you wanted shading you had to use rows of etched lines - closer together for darker and further apart for "lighter" shading.
You can get brushes for both Photoshop and Illustrator that emulate this - do a Google search for "intaglio brush" or "etched brush". You can also get similar results with some of the Photoshop stroke filters (specifically the Artistic and Brush Stroke ones).
The font in the main banner looks like Barrelhouse or similar; again, take a look through some of the font sites out there to see if you can find similar fonts.
The ornaments can either be made or purchased; I personally like Letterhead Fonts a lot since they have a good selection of both period-looking fonts and ornaments, but there are others out there.
Finally, it appears that they've added a grunge look by overlaying a distressed texture over the entire design. Again, a GIS for "distressed texture", "weathered texture", "crumpled paper", etc. will yield plenty of results.