There are actually a lot of cool online tools to aid with creating image maps but for those users of GIMP you have a pretty easy to use and configurable image map tool right at your finger tips!
In this video I show how easy it is to use GIMP to create image maps for web sites.
Make sure you check out the Image Map Plugin Page to learn more about this cool feature.
I was poking around the internet and thanks to Google I found very quickly this Image Map Tool site that lets you create image maps for your graphics. I quickly created a simple graphic, uploaded it to the tool and create maps for different tag categories on my site. I then copied and pasted the HTML into my blog post and viola, works like a charm!
Feel free to check it out and donate if you like it!