Apologies if you've already seen these, but I thought they could be quite useful for those who are just starting with Moodle.

The following is a post on the Moodle UK list from Tony Delahunty, E-Learning Development Co-ordinator or College of North West London 

We have developed a bunch of new Moodle themes, including various high-contrast (HC) combinations and large font, trying to replicate various accessibility needs as they are offered in the Techdis Toolbar.  This is intended to promote both the personalisation and accessibility benefits for our students. 

These themes have been implemented for Moodle 1.8.2, and haven't been tested with earlier versions, but may well work without too much adjustment.   We're making these freely available for use: see a preview at http://moodle.student.cnwl.ac.uk/moodle/mod/resource/view.php?id=11368 and download them at http://moodle.student.cnwl.ac.uk/moodle/mod/resource/view.php?id=11369