If you have a computer of your own, there are numerous free versions of Prolog
available on the web.
SWI Prolog is available for download over the Web. More information is available at
:
http://www.swi-prolog.org/
For Macintoshes, the best free Prolog for System 9 or earlier is Open Prolog, available
from Trinity College Dublin at:
ftp://ftp.cs.tcd.ie/pub/languages/open-prolog/OpenProlog.sea.hqx
For System X, a version of SWI-prolog is available.
The manual for SWI-prolog can be accessed from the SWI-prolog Help menu.
There is a Prolog course (at Birmingham University) available over the web at
http://www.cs.bham.ac.uk/~pjh/prolog_course/se207.html
This site also has information about other public domain Prologs.
And another by Patrick Blackburn, Johan Bos and Kristina Striegnitzat called ‘Learn Prolog Now!’ at
http://www.coli.uni-sb.de/ kris/prolog-course/
Amzi!’s site provides several Prolog learning aids:
http://www.amzi.com/products/learning_products.htm
There is also a guide to Prolog programming at
http://kti.ms.mff.cuni.cz/~bartak/prolog/index.html
Finally, the WWW Virtual Logic Programming Library contains links to all kinds of logic programming resources: