Navigation is an important element of he websites. Done it properly the navigation will help the users find what they need in your pages. Some resources for navigation are below:

Webpages navigation

Sliding Doors of CSS – Sliding Doors of CSS, Part II

Vertical CSS menu with flyout submenu

Inverted Sliding Doors tabs

Bulletproof Slants

CSS Tabs 2.0

CSS Tabs with Submenus

Free Menu Designs

Mini-Tab Shapes

CSS navigation menu

Nifty Navigation Using CSS

List-O-Matic

CSS horizontal navigation list