I am interested in developing an app for my new iPad purely for my own use. (well to start with at least)
I think the best option is to develop the application using HTML5 / Javascript and CSS, and use a service like appMobi or PhoneGap to compile it for IOS. They both have an online service that can make the build for you without needing you to own a Mac.
You have also the added advantage that you can compile your app not only for IOS, but for Windows Mobile, Android, Blackberry and even the good old web.
You have some Javascript libraries like JQTouch that allows you to easily implement the IPhone look and feel in your web app. Normally you can't access the native API from Javascript, but these solutions (appMobi and PhoneGap) offers a Javascript API that you can use to access Camera, GPS, Gyro, etc...
I think normally serious apps are coded for many platforms, and if you don't have the structure to pay to 4 different skill sets, it makes sense to code in HTML5, and from there you have a more future and device proof solution. Even if you "can" pay different developers to code in diffrent mobile platforms I would prefer to do it in HTML5.
Oh, and also take a look at applicationcraft.com, pretty cool online IDE (wysiwyg) connected to PhoneGap, really easy to develop prototypes. The generated HTML/Javascript is not very usefull to continue editing it outside their IDE (a bit complicated), but, again, for something very simple or a prototype it's something you must check out.
Good Luck