Many other books on PostScript make example PostScript code available. ``Thinking in PostScript'', by Glenn Reid, is the only book I know of that allows its examples to be freely distributed. (See Section 5, ``Books''.)
All the examples in ``the blue book'' are available from the Adobe file server (See Section 5, ``Books''.)
See the question ``How can I browse through PostScript programs?'' in the comp.sources.postscript FAQ.