National Geographic has made available free-as-in-beer online USGS topographic maps for everyone to download and print out. Interactively select a region and get five pages of high resolution mapping data. Page 1 is an overview index map. Pages 2-5 are higher resolution quadrants of the index map.
7.5 minute resolution. Sized for 8.5x11 printing so you don't need a huge poster printer.
Requires only an e-mail address to get access.