Help with rollover effect

[xxtomxx]

Hi, I have a map of England with only the outlines of counties on it, beside it I have the names of the counties used as text links to other pages. What I would like to have is a rollover effect on the text links that highlights the appropriate county on the map.
Can anyone tell me the easiest way to achieve this effect? I am using Dreamweaver and I am sorry if this is daft question.
Thank you for any help
Tom

[adwatson]

If the map is just one fairly small image, probably the simplest solution would be to create alternate versions of the map with each county highlighted. Then when the user rolls over the links, use javascript to swap the image SRC to appropriate rollover state. And the reverse when they roll off.

Another option would be to use CSS to position the rollover images (a small highlighted version of each county) in layers over the map - set them to visibility: hidden initially and then turn them visible with javascript as needed. More fiddly getting all those images positioned, but may be faster if the map image itself is large.

[xxtomxx]

Thanks it works a treat I made the map smaller and used the swap image behavior in Dreamweaver.
Tom