In directory docs/psdocs/ you may find new information in the gnuplot output postscript file guide, list of postscript symbols in different encodings.
Improved FAQ. Please read it before asking your question in a public forum.
There are plenty of new demos *.dem in the demo/ directory. Please run them, for example by
load "all.dem"
before asking for help. Plots produced by the demo scripts can also be viewed at http://www.gnuplot.info/demo/