Fantasy writer Joseph Robert Lewis has a great blog for writer's and readers. You'll want to bookmark it for sure.
In the writer's section he has a super simple tutorial at his blog for anybody who wants to get an ebook up at Amazon.
Don't let the tutorial title scare you off. It's called Bare Bones Guide How To Turn A Word File Into A Mobi/PRC File For Amazon Kindle In 10 Easy Steps. But the most important word in the title is Easy. It really is laid out in 10 easy steps and you'll be ready to upload.
Go over to Joe's Blog and get that ebook ready for Amazon. You've go no excuse now.