The most common project for web designers would be business layout design. What the client wants is normally clean, sophisticated and reliable business image. These tutorials I found includes many simple yet useful tips. Hope this could help you fulfill your clients expectation.
How to Make a Green & Sleek Web Layout in Photoshop
Create a Clean and Colorful Web Layout in Photoshop
Make a nice corporate website for a product
Modern Web 2.0 Web Layout
Design a trendy business & finance layout
Corporate Business Layout
Photoshop tutorial to design a clean business layout
Business Layout
Create a Business PSD Layout in less than 10 minutes*