I want to build a website. What is the best website to go to?
This site would probably be want you are after:
If you want to use Joomla or WordPress, check out the MUO guides on them.
If you want to do it the easy way make a blog on wordpress or blogger. Even go with Tumblr if you want to make it super simple. If you are looking to go with a more advanced site, I would follow Jeff's advice.
Step 1: Learn some web programming (check links below). You will need to know at least HTML.
Step 2: Find a web host. A web host will hold your files and allow visitors to execute your code. A free web-host should be fine for the start. You will chose a domain name and will have the option to upload those files.
Step 3: Advance your understanding of how web servers work and mess with some other open source code.