This is my 1st space image here on caedes. I know there's some things that could be done to make this better, and if you think of them, let me know!
Hope you like it though.
Go have a look at Alyn's "Advanced Planet Creation" guide at http://www.deviantart.com/view/11885274/. The tutorial (about 5 MB) can be downloaded as a .zip file by clicking the "Download to Desktop" button just below the image. Once unzipped, the tutorial is webpage-based. Open up the "index.htm" file in your web browser.