Here are some general Second Life resources.
The official Second Life website. Login to see your account, your friends online, the latest news from Linden Labs, upcoming events, and more.
My Second Life
See and edit your profile online.
Second Life Grid Status Reports
Linden Labs reports on the status of the Grid. Problems logging in or with shopping transactions? It might not be you; check the Grid Reports.
Second Life Wikia
The new wiki of Second Life.
Second Life Wiki
The old wiki of Second Life. There is still a lot of great info here.
Second Life Community
The official Second Life blogs, knowledge base, and forums.
Second Life Support
Have an issue? Contact support.
Second Life Jira
Found a bug? Investigate it or report it here.
Second Life’s You Tube Channel
Tutorials, previews, and more.
Second Life Marketplace
Shop for your avatar on the web.