I would start by checking out coindesk. There is also a subreddit for it. Lots of useful information out there. You should also check out @crypt0 here on steemit or YouTube. He shares lots of great info as well.
https://www.youtube.com/user/obham001

Here's a link to a complete explanation of what ethereum is and how it works. http://www.coindesk.com/information/what-is-ethereum/

Cheers