Well the usual start is to do a little research through some search engines on the internet.
You can look up "
Artificial Intelligence", however you could end up with miles of links to peoples dreams of a better A.I, science fiction and obvious alot of sites saying they are free and are attempting to sell something.
I would suggest perhaps looking through
www.archive.org at the site "www.botspot.com". The new version of that particular site attempts to sell different programs that are either
Expert Systems,
Chatbots or
Agents (data miners) and is not as good as the original site that contained more academic information.
You should also perhaps look at the more renound Artificial Intelligence projects that have been done (mostly by M.I.T.) such as the chatbots
ALICE and
ELIZA.
You might even want to concern yourself with the history of "the computation engine", of course I don't mean going as far back as
Charles Babbage however you could look into
Alan Turing's suggestion of
Intelligent thinking machines which has gone on to create "
The Turing Test".
There is a test carried out each year with a number of different entrants called the "
Loebner Prize", which uses the "Turing Test" to test the entries with the chance of somebody or team winning a prize.
You should also go to your local library (with either your library card or some forms of identification so you can get a card) and see if there are any books in the computer science section.
If you aren't in school, there is always the opportunity of enrolling on one of the computer courses at a local college which also would require you to learn the information for yourself while finding the source material.
You might also want to check these sites:
http://www.cs.nott.ac.uk/~gxk/courses/g5aiai/002history/eliza.htm
http://www.alicebot.org/
http://www.aaai.org/