James Craig of Cookiecrook has written a very nice tutorial called Accessibility Internet Rally 2003 Advanced Training Material. For those of you trying to improve the accessibility of your websites this tutorial can be very helpful because it collects the recommendations in one spot.  The notes cover such topics as forms, tables, semantics, CSS basics and accessible CSS. If you are the type of person who needs to see a real-life example to help you understand a concept, these notes are available in presentation mode, web page mode or as plain text.