There are many search toolbars that will also do that for you. Probably the most popular is the Google toolbar. Search for the term and hit the highlight button (looks like the point of a felt tip pen) and all instances are highlighted in yellow.
Using IE, Firefox, etc., once you get to the page you're looking for, you can Ctrl+F and a find window pops up where you can jump to the first instance of the search phrase, then next, etc.