You will want to use Google Analytics. All you do is add some code at the end of each of your pages, and Google will provide you with detailed info.
If you want to add customized search to tour site, use Google Site Search.
You will also find the Webmaster Tools section helpful, including submitting a sitemap of all your pages.
Finally, you can also add Google Maps. It's easy. Here's my article on how to do it.
Bravenet is a warehouse of free tools you can add to your website. They have all kinds of free web applications like guest books, photo albums and calendars.
You can create your own talking spokesperson with the help of SitePal. SitePal is an easy-to-use service that allows you to create a speaking avatar for your website and empower your online communication.
Do you have a Paypal account yet? You should. You can send or receive money with your email, and it is a much easier way of handling credit card purchases. They have an easy-to-use shopping cart too.
Stop by the Logo Garden if you are not happy with what you have. You can make a logo for free, in 8 minutes. They also have lots of samples to help you see what is possible.
This is an extremely valuable tool that allows you to track your emails. You will be able to tell if your message was received, if it was opened, how long it took the person to read, etc. You can even get your email back, even if has been read!