Familysearch.org is a free site and it is easy to find their Research Wiki. Go to familysearch.org and I recommend that you join as it is free. Go to the top right hand corner and click on the "Join for free" tab. You only do this the first time and then after that you sign in with your username/password.
After signing in click on the "Search" tab and then you will see the 'Wiki" to the right of the banner near the top of the next page. The Wiki page will open when you click on the tab "Wiki". You now have access to research advice and how to find a record collection of 77,250 articles.
The Research wiki page also offers search tips, opportunities to share your research knowledge with others and research help and tools.