Ok, seing as I do a lot of stuff in Photoshop and the fact that I'm self-taught, I thought I'd help out anybody who's starting out working with Photoshop. I will start out by posting some good links to certain photoshop-tutorial pages that I've found to be useful. I will also answer questions and give tips on how to do stuff.
The main reason I have learned photoshop is actually photo-retouching so most of these tutorials will probably be about that. I'm also administrating a forum and I needed to make some nice buttons and a logo for my forum. Bear in mind that if you just learn how to use certain functions, you can apply them to any other work you might want to do.
I will expand the General Tips as I think of them, the tutorials I refer to when answering questions will be added to this post as well. I might add further questions and their respective answers to this topic as well, if they are relevant enough.
General Photoshop tips!
Always work with large pictures. You can always resize them when you're done and it's a lot harder to work in low resolution pics.
There are a lot more tools in Photoshop than the ones that are visible on the tools-manu. Press and hold the mouse-button to access the drop down menus on the tool you want to use.