IMHO you first need to understand design, its various sub fields (i.e. typography, colors, layout), user experience design/interaction design/usability, and finally how all of this applies to the web. You can learn the basics by reading books but the only way to truly understand and master is by study this things in the world and by practicing them. Start thinking about design, analyze it in your daily life, do your own makeovers of sites you use, design a blog theme, etc, etc.
As for web typography, you want to check of the latest generation of font embedding because that's where the real magic's at. The most known web font solutions are: CSS3 (font-face), typeface.js, cufon, flir, sifr, Google Font API, Typekit.
Here's a list of quality books on design and typography:
A History of Graphic Design
Before & After Page Design
Designing Brand Identity
Emotional Design: Why We Love (or Hate) Everyday Things
Graphic Design Solutions
How Designers Think
Information Dashboard Design: The Effective Visual Communication of Data
Making and Breaking the Grid: A Graphic Design Layout Workshop
The Complete Manual of Typography
The Designer's Guide to Color Combinations
The Elements of Graphic Design: Space, Unity, Page Architecture, and Type
The Elements of Typographic Style
The New Typography
The Visual Display of Quantitative Information
Thinking with Type: A Primer for Designers
Typography Workbook: A Real-World Guide to Using Type in Graphic Design
Books on web design: About Face 3: The Essentials of Interaction Design
Ambient Findability: What We Find Changes Who We Become
Bulletproof Web Design
Cascading Style Sheets: The Definitive Guide
Designing Web Usability
Designing With Web Standards
Designing the Obvious: A Common Sense Approach to Web Application Design
Designing the User Interface: Strategies for Effective Human-Computer Interaction
Don't Make Me Think: A Common Sense Approach to Web Usability
Homepage Usability: 50 Websites Deconstructed
Information Architecture for the World Wide Web: Designing Large-Scale Web Sites
Information Architecture: Blueprints for the Web
Interaction Design: Beyond Human-Computer Interaction
Rocket Surgery Made Easy: The Do-It-Yourself Guide to Finding and Fixing Usability Problems
The Essential Guide to User Interface Design
The Inmates Are Running the Asylum
Thoughtful Interaction Design: A Design Perspective on Information Technology
Web Form Design: Filling in the Blanks