a good start would be with basic x/html and css over at
w3schools
after you've awed yourself with the cool designs at
css zen garden, head over to
a list apart for the theories and all that.
of course you can try to look around the cool designs and what others have accomplished over at
open source web design.
and as already mentioned, php has nothing to do with html site design.
css and javascript would be a pain, since they don't always work the same across browsers.
but just like
Cheetah8799, i try to avoid javascript myself. the incompatibility and the fact that most people turn off javascript nowadays ...
more css learning can be obtained from
css/edge. you might also want to look at
the web standards project for articles and links to resources related to web standards.
if possible, try to avoid the css hacks (which you can read up at
p.i.e website, among others). trust me, those will drive you crazy despite the fact that it can help make your css work across major browsers.
my suggestions would be to try designing sites with basic html (with no scripting like php or whatever - just pure html), add in some css to it, play around with it, get comfortable and frustrated with it. after that, add in the php and other scriptings, etc).
oh, one more thing: start designing in mozilla then port it to msie, not the other way around. msie should always be one of the last browsers you test on. you might also want to download opera and see how it looks like.
i would add more, but i guess i've overwhelmed you enough with this lengthy writings ,p