Really, doesn't exist a many websites than I use for my carrer. For that, the website than I use more is scholar google, cause in it you can find many digital papers and digital books about investigation, theoria, publications, etc. So, when I need read about a specific theme I enter to the website to search papers related with it. You can do this in normal google too, but in scholar google you can find literature more specific, for particular theme by experts.
The website is so simple to use. Got the same logical than google: A "whrite's bar" where you whrite the especific words about the paper than you hope find and after the page shows you a lot of link with a title of the paper. You choose the titles than you thinks will help you with your needs and makes a click in it and then the website shows you the page of this paper and you read it. So simple. This is a simple way ti find the papers than you need.
I use this website all time, especially when I need read about themes than I don't know a lot.
Sorry, but aren't many websites for sociologist