How to start?

Hey guys,
I have an idea for an app that I really want and I figured that since it didn't exist, I may as well try to make it myself.
But here's the problem - I've never made an app before and I have no idea how to start. I know that app building is probably a very difficult thing to do, but everyone has to start somewhere right?
Here are my questions:
Where is there a GOOD how to guide?
What software do you use to build the app and where do you get it?
How do you find out if Apple will even accept the app you send? Mine is potentially controversial and I don't really want to spend days working hard on something that's only going to be trashed because Apple wants to make Stephen Conroy look like a reasonable, open minded guy. Is there a way to get an idea before you build, or do you just have to go in blind?

Thanks so much, in advance, for your help.
-Alice