Free all-sky maps, visit Skymaps.com and click on the download latest issue links partway down the page. For an interactive sky map, click on the "Mini Astroviewer" box to the right.
Detailed star charts
The detailed beginner star charts by Andrew L. Johnson show stars down to magnitude 7.25; about the limit of naked-eye visibility under very dark skies. For most of us under light polluted conditions, it's a great set of charts for finding our way around with binoculars or a very small telescope. Find planets and see conjunctions of planets with the moon by watching the current Eyes on the Sky video. Download free Greek Alphabet reference guide here.
The star charts above utilize the Greek alphabet system to denote the brightest 24 stars for most constellations. To assist in interpreting these symbols, you can download this free Greek Alphabet reference guide here. File is for 11 inches x 8.5 inches paper, in PDF format. File size is 2.3MB. See below for a preview of this chart, or click on it to download the PDF.