Jackie,

I am using Word2000 right now, but this method should work in 2003 as
well.

EditReplaceMore

Type the word you want to hightlight in the find what field.

Type ^& in the replace with field. With the cursor still in that
field, click formathighlight, then replace all

You may find the following Add-in useful:
http://gregmaxey.mvps.org/Find_it_tool_bar.htm