So yesterday, we got the links to get started with cross platform development using Qt, but there here are some Maemo specific resources as a follow-up.
Start with Qt-development on Maemo5 by downloading the Qt SDK from here and then MADDE for your system (available for Windows, Linux & Mac OS X).
You can create, build and test your project in your native environment with the QtSDK.
With MADDE you can compile it for the device.
Again Forum Nokia has a ton of stuff available to help you get familiar with the environment through examples and courses on Qt for Maemo.
There is a strong community around Maemo and they can support you with your question, but be aware that there is loads of documentation out there already.
As Maemo is an open source project, a good source of help is on freenode IRC-channels #maemo, #qt-maemo and as it gets closer to the event #nokia_mdc.
There is also a wiki page specifically for MobileDevCamp.fi
Oh, and if you are scared of C++, Maemo also supports Python (but then you lose the cross platform comparability stuff, and you will see why that is so important next week!)
There is less offical pages around this, but from the Maemo Forums, here are a couple of threads that can work as getting started guides – Qt Designer/Python for Windows XP in 30 Mins and Qt4 Hello World in 30mins (from a rusty programmer).
A longer tutorial can be found at here