For starters download GIMP (
http://www.gimp.org/) GIMP is the GNU Image Manipulation Program, imaging Photoshop, but free. I have Photoshop CS3 and I can tell a big difference, but if you have PS7 or older, you'd like GIMP.
A specialized build of GIMP called GIMPShop is available here
http://www.computerdefense.org/gimpshop/gimpshop_2.2.8_fix1_setup.exe (Win 98+, Newest version). GIMPShop is designed to look and act like Photoshop.
There, now you have a decent image editing program...
2nd, CSS is a big part of web design, but remember, web standards suck. No site can ever be validated with both correct xHTML & CSS.. it's just not possible. (Any good, normal looking site.) Don't throw standards out completely, but do realize there are a lot of small hacks you'll have to use to get your IE6 sites looking like IE7 and even Firefox. Only one or two known browsers are perfectly CSS compatible. (See the Acid2 Test, and Opera.)
If you'd like a basic tutorial of CSS just ask, and I'll gladly put one in the Off-topic discussion board.