I didn't make it!
I have a few things here, first of all: I'm a noob modder and wants to make his first mod. HELP!
Second: If anyone is making a mod and needs voice overs, PICK ME!
Third: I have a mod idea, well it's kind of... BIIIIIG! Hehe... Its a new planet...
Oh and btw it's for KotOR...
I can help with your first request, you can find basic modding tutorials at KOTOR Files here.
As for your third point, creating new planets in KOTOR is quite difficult due to the lack of any official modding or level creation tools. Each new area would have to be coded by hand. You might want to check out other mods for a basis on what you want to do such as the Mandalorian Base mod.