I found an excellent resource for Cascading Style Sheets (CSS), which has a list of great tutorials and examples for the beginner or intermediate CSS user. These are the basics when any developer or designer should have a handle on:
If you are looking for something a bit more advanced and on the bleeding edge, check out CSS Tricks, an excellent site with video tutorials and LOTS of other great CSS and design-related things. The author of the site is into jQuery too, so he has a lot of blog posts about tips and tricks related to that. Great stuff!