Starting programming, is an editor realistic?

Hi everyone. I'm just starting programming (only done NetLogo, which is very simple, before). I've read the Kochan book on Objective C and am starting the Stanford U iPhone App development. That being said, I am still a novice. Novice novice.

I have a goal for a Mac/iPhone/iPad game, but it will require a lot of levels that use very simple 3D structures (cubes and whatnot). I'm wondering if it is realistic to make an editor for setting up these levels. Something where I just had a plane (the 'ground') and I could click on a button to create a cube and then drag it to the location I want on the space.

So, that's pretty much it. Can I make that without years of work or is this just a pipe dream?