Quickly Change One Style to Another
The Problem:
Our annoying affiliate has sent us a slew of documents that use the wrong styles. I need to change all the styles to the right ones for our marketing communications template.
The Solution:
Word's Replace feature can change the styles for you, and a macro using Replace can whip through all the documents in less time than it takes to make a cup of decent coffee. But Word 2003 and Word XP offer another possibility that you should know about: choose Format 
Styles and Formatting, click the offending style name, click the drop-down arrow, and choose the "Select all instances" option. With all the instances of the style selected in the document, click the style to which you want to change these items. You probably won't want to use this feature for changing entire documents, but it's good for lighter-duty work.