New User FAQ:
Q: Why does SL run like shit?
A: Terrible viewer optimization, sculpts, and terrible object optimization. Lower your draw distance and object detail for free frames. Also try out avatar impostors.
Q: Which viewer should I use?
A: Firestorm is the go-to, but it's up to you to decide what you should use.
http://wiki.secondlife.com/wiki/Third_Party_Viewer_DirectoryQ: How do I make money?
A: Provide people with a service or a product and someone will be willing to pay you. The only issue I see people running into is making themselves known.
Q: How do I make things for Second Life?
A: Any image editing software can make textures for SL so long as it can save in jpg, png, or tga format. Image resolution must be in powers of two (maximum being 1024). Height and width don't have to match. There's an in-game primitive manipulator and editor. It's really limited but you can make basic structures with it. There's sculpts too (
http://wiki.secondlife.com/wiki/Sculpted_Prim ) Generally speaking they're terrible but they have their advantages. Only consider using them when you're using mesh with a ton of animation states. Mesh objects can be made in nearly any 3D modeling program. Upload in .DAE format. And finally there's Second Life's scripting language, LSL.
http://wiki.secondlife.com/wiki/LSL_Portal