OSDev.org

Maybe this can be a sticky topic, so people won't have to look for a topic about tutorials once this board grows. Anyway:
Found a good tutorial on Win32 API programming.

-Kon-Tiki-

Well here http://cs.smith.edu/~thiebaut/ArtOfAsse ... ofasm.html is an assembly tutorial, probably the best one there is, this is very helpful for high level programmers as well.

Here http://zoo.cs.yale.edu/classes/cs421/pa ... f-asm/pdf/ you can find a list of each chapter as a pdf file.

http://www.php.net/manual/en/

I used to use this manual all the time when learning php. It is the offical manual/tutorial.