you can still scan 1 page for free from Casts Bobby.
http://bobby.watchfire.com/bobby/html/en/index.jsp
you can also read the W3C page for "Evaluating Web Sites for Accessibility", which should help you do the same thing the progam you want will do. Best of all. If you do the compliance checks yourself, you dont become dependant on a program which one might be free, and next day charges.
http://www.w3.org/WAI/eval/
and has a listing of tools which validate.
http://www.w3.org/WAI/Resources/#er
Are you interested in CastBobby311build7?
thanks go to member Goslow who has sent me the link to check out. you can obtain the file here, it is 6.4megs
CastBobby311Build7
If clicking on the link does not dowload the file, you will need to RIGHT CLICK and Save AS to obtain the file
thanks Goslow!