I bought a book recently called "Mixing Secrets for the small studio" by Mike Senior. I think for me as a newby has a lot of information in it and is easy to read.
Along with the book , he also has a website
www.cambridge-mt.com which has a lot of practice sounds that go with the book.
What I like about it is that there are raw tracks that you can download and put in your DAW in order to practice mixing. The best part is that the website is free for anyone to use even if you didn't buy the book. All the raw tracks are in different styles of music , which gives you a wide spectrum of mixes you can practice.
Hope this was useful.
Danny
On the website you go to free resources