Once you have a web site up and running you’re going to want to have some basic understanding of how it is being used.
The first tool I recommend is Google WebMaster Tools. It will help you understand what other web sites are linking to yours. There are also a couple other tools that can do this, like GooLinks and Moz’s Inbound Link Profiler.
For more advanced analytics—including how many people are visiting your site—Google Analytics is the king. It requires placing a code snippet on every page of your site. Generally this is pretty straightforward to do, and most site builders even have a configuration setting for this so that you don't even need to dig into your code directly.
To find out specific pages that are linking to you, you can use Googles search operator site:. So if huffingtonpost.com shows up on your list of inbound links, try searching for your org's name or web site on HuffPo pages only, e.g.