At the first Dutch DrupalJam, I gave my workshop theming Below, you can find the slideshow and the resources for the live demo, The presentation is Dutch though. You can also find the presentation (and more) on slideshare, so you can re-use, or embed it on your own site.
During the workshop a lot of sites about CSS passed by. Below you find a shortlist of the most important CSS resources. For a more comprehencive overview, you can see my CSS tag on Simpy. Alistapart QuirksMode W3C validator (HTML) W3C validator (CSS) Browsershots overviewA note about the attached files: * theme_workshop_drupaljam_2007.odp and pdf are the presentation themes.tar.gz contains the modified Garland themes, one version for each step.* drupaljam_thm_helper.tar.gz contains the helper module.