Rehab.Help.org is a community organization dedicated to empowering people suffering from substance abuse addiction with tools and resources to start their personal journey toward recovery. They create and publish comprehensive, unbiased, free web-based resources that have been featured and are referenced by many governmental agencies and organizations across the web.
https://rehab.help.org/guide-to-alcohol-addiction/
https://rehab.help.org/guide-to-heroin-addiction/