The quick mask mode in Adobe Photoshop lets you quickly make minor adjustments to the selection.
Articles > Webmaster > Multi-Column Layout
The search for good multi-column layout has become the holy grail of CSS-based HTML, and a lot of articles have been written about the subject. I'm not going to repeat all that here — you can follow the links in the references section below.
What I provide is a nifty test page where you can experiment with different CSS and see how it behaves. Where I am aware of browser-specific issues with any given technique I mention them.
See also:
Other intermediate webmaster articles:
Other intermediate webmaster resources: