Yes, you can run a site off an Excel document, but it's rather involved and has its own share of problems.
I'd almost always argue in favour of transposing the Excel data into an Access database. After that point you can create ASP pages which can read from and write to the databse.
You will need to host the site on Windows servers with full ASP support and the ability to upload at least one Access database.
Access is fine for relatively small sites but large web applications are always better off using MS SQL or MySQL as the underlying database.
Unless you start getting hundreds of concurrent hits though, Access is fine and you can migrate (upsize) to MS SQL later if and when the need arises.
1&1 click here offer one of the best value Windows hosting accounts I know of and you get full FrontPage Server Extension, ASP, .NET and Access database support, among other things. You can also get the latest copy of FrontPage if you take out a Windows hosted business plan and their control panel is easy to use.
Getting started in dynamic web design is the one area of web authoring that usually brings things crashing down like a house of cards. At the end of the day, anyone can use a WYSIWYG editor to drop elements onto a web page and produce something like a website. The same cannot be said for dynamic sites though, which depend entirely on a fundamental understanding of databases, how and why they work, and how to hook your pages into them without compromising performance and (more importantly) security.
It's a big topic and I'm more than happy to help if you come unstuck.
If you'd like some links to tutorials, just ask, but Dreamweaver (since you mentioned it) has a full dynamic site walk-through in its help files and shows you how to do the necessary work in PHP, ASP/.NET and ColdFusion, as well as offering help on setting up a testing server environment on your own PC.