This is a list of resources that work for me. I know there is lots more out there, and I am always discovering new things. So be sure to look around!
This is the website of the Zentangle originators, Maria Thomas and Rick Roberts. Lots of useful stuff
This website lists all the tangle patterns in alphabetical order. You can click on a letter of the alphabet at the top and look up any tangle. The tangle link will take you to all the info about the tangle, who invented it and what they were thinking about, and most importantly, the step by step instructions for how to draw it. The website also has a random tangle generator on the left so you can let fortune decide which tangle pattern to use next.
Margaret Bremner, CZT, is a very creative artist with all kinds of interesting ideas that you can experience in her Zentangles. She constantly amazes me.
I often enter the weekly Zentangle Challenge, now going on for over 300 weeks. There is no winner, and there is no criticism. Only lots of sharing and praise for one another, in keeping with the wonderful Zentangle community's philosophy of support for one another. I too believe that emphasizing an artist's strengths will help them to grow and flower, much more successfully than harsh words, no matter how "true."
Ellen Wolters on YouTube
Watch as Ellen draws Zentangles for you a d makes them absolutely crystal clear. She is a marvel of skill and I love the music she uses. I have had to play it on my Kindle and Shazam it on my phone so I can download it and just listen while I tangle. Here's an example of Ellen demonstrating a tangle pattern you know, Crescent Moon. Just watching her draw teaches me so much. If you Google "How to Draw Tangle Pattern Whatever" Ellen's YouTube's will often come up.
The Zentangle App (Mosaic)
Download Rick and Maria's great App. The do frequent videos showing all kinds of interesting things about Zentangle. Available for all Mac Platforms and Android phones, but not Android tablets, darn.
One Zentangle A Day by Beckah Rahula
This is how I first learned basic Zentangle. It is a 6 week course in a book with step outs for lots of tangles and many ideas to try out for yourself. Get it on Amazon here.
Cheryl Wilson, CZT
Cheryl is my Zentangle teacher. She helped me to slow down and really appreciate and above all enjoy the Zentangle process. Cheryl's blog has lots of great Zentangles. She has a very steady and beautiful line quality when she draws, and she is always putting things together in creative, unexpected and fun ways. Cheryl is a painter and her oil paintings can be seen here.