You know how to use scripts? Purple Yin (www.purpleyin.com) is one I used and I liked the look of it and I got it working on a couple of sites. I think it uses PHP language. It was not too hard to set up. No fees. If you don't know how to use scripts, you can hire a programmer like my brother and me. Or post here, and I can try to help you.

I don't know if Guest Books are worthwhile or not. Maybe they are for musicians, since good reviews are helpful.