1.  I need some PostScript information
http://www.prepressure.com/
This site is very good.  It has information like
Postscript Troubleshooter (local)
What is PostScript (link)
PostScript Errors (link)
History of PostScript (local) 

2.  Another great PostScript information page
http://www.cs.indiana.edu/docproject/programming/postscript/postscript.html