Obligatory xkcd link: http://xkcd.com/927/

I currently use LockCalendar for this (requires jailbreak, available in Cydia) and love it: http://preview.tinyurl.com/d2ko29

There's also IntelliScreen (requires jailbreak, available in Cydia): http://intelliborn.com/intelliscreen.html#step1

What you need is something like this: http://www.paloalto.com/business_plan_software/

I've used it, and it's pretty good.

It will create the entire structure for you, so all you have to do is fill in the data. It might have sample business plans for a web based business, which you can edit to suit your objectives.