There have been some good responses to this post. I have to agree with all that discourage you from trying to build a professional site with no experience. The drag and drop programs allow for customizing content but really aren't made for someone who has a specific design in mind as you indicate you do (unless you are skilled in the areas of web design and programming). I would think you would become easily fustrated very quickly.

You also have to have a good hosting account setup that will allow for you to install the software such as Mambo which requires PHP and MySQL. To truly edit the program in order to customize the look and feel you need to know HTML, PHP and database (MySQL).

If your biggest concern is communicating with a developer on how you want the site to look, consider investing in photoshop and a good 'how to' book and design the look of the pages. That's how many web designers start in the first place.

Good Luck