I remember Wendler saying that “fixing someone’s body is 10x more valuable than all the therapy he could ever get to fix his/her self-esteem”. Something along those lines.
Personally nothing has helped me more than blocking stuff.
Books are alright, but too time consuming and long-winded.
In the end, the most practical for me was the following,
Other Browsers (I haven’t tried it):
change the hosts file
IMO Nothing beats having the devices that could distract you off.