To create a planet in Photoshop you need a planet terrain texture, some PS skills and digital painting techniques. Although it is not very hard to make your own planet in Photoshop it might require a lot of time to create a realistic looking effect. So it is easier to choose a ready to use premade planet stock image and integrate it into your photo manipulations along with other elements like stars, meteorites, galaxy space backgrounds, space ships and so on. So here is a list with creative planets that you can use for free. The list also includes some useful editable PSD files.
Recently I have created my first Photoshop tutorial on how to create a space landscape with planets, stars, and so on. I don't know if you guys like it because the feedback was kind of low, but I might say making this tut was not an easy task for me. So I started reading other space tutorials to improve my skills. Here is the list with the most interesting tutorials that I have found. If you want to learn how to create in Photoshop space elements like galaxy, planet, meteorite, nebula, cosmos, star fields, comets,supernovas and so on, read these tuts. What I love is that many of these elements are made from scratch so they are really useful.