DOOM was originally released as a shareware title, therefore you can
still get the first "episode" of DOOM free of charge. You can download
it here,
ftp://ftp.idsoftware.com/idstuff/doom/doom19s.zip This will
give you an idea of the game, although there is alot more available in
the full version and DOOM2.
In the late 90's idsoftware released the source code for the DOOM
engine (very kind of them hehe) This allowed fans to create their own
levels, ports, add-ons and conversions for the game. FREEDOOM is
a version of DOOM compiled form this source code. It does NOT contain
the original game, however it has new single player levels and allows
users to play the fan made levels and other ports. Get it here
http://freedom.sourceforge.net I can't stress this enough though, great
job from the developers of FREEDOOM, but if you like it, the original
full game is a MUST!
DOOM can still be bought in a collectors edition format from many
gaming outlets. It can also be ordered at the id homepage,
www.idsoftware.com/games/doom/doom-collectors/ . This collectors
edition contains DOOM, DOOM2, Ultimate DOOM and FINAL DOOM. You can
also purchase them individually. Alternatively you may want to search
on ebay to try and get a pre-owned version of the game
www.ebay.com or
www.ebay.co.uk .
Check the Ports and conversions section for other versions of the game.
Having bother finding it, email me and i'll put up links to other
online stores (Don't email me asking for pirated copies, i won't
respond!)
Check the troubleshooting section if you're having problems with any version of DOOM, or email me!