since ive seen a few guys giving away links to good tutorials, i decided to show you a few good ones i've found on DeviantArt.
here is the first:
http://foervraengd.deviantart.com/gallery/4251501its a collection of anatomy tutorials. it is a must see for manga lovers, but it applies for almost anyone.
http://photoshop-tutorials.deviantart.com/ is THE GREATEST compilation of photoshop tutorials in DeviantArt, and possibly on the WHOLE internet. many of those tutorials were made by professionals.
http://artistshospital.deviantart.com/this is another one of the "Mighty Ones" around dA. instead of focusing solely on tutorials, it also has stock images and other stuff that you might like.
seriously guys: hope this helps. feel free to point out other tutorials you find.