For developers without a Linux-background and supporting hardware, getting into development on Maemo is most easily achieved by using PyMaemo, the Python port for Maemo.
Once you have an application, one remaining hurdle is the proper packaging of your app. This needs to be a Debian package, a *.deb file. As it is impossible to build such a package on Windows-based systems (different concept of permissions, no tools), you need to build it either on a Linux system – or you can directly do it on your Internet Tablet using the handy PyPackager tool from BenoÃ®t Hervier, aka Khertan. With it, you can simply select a source directory that then gets packaged into the final DEB file suitable for distribution.
However, you first need to properly structure your source directory to achieve maximum Maemo/Hildon desktop integration. Some time ago, I wrote a wiki page on the maemo.org community site to explain this, using the mClock build process as an example.
Hope this saves some poor soul from losing his mind – mClock took me 2-3 evenings for the application and at least 5 evenings for proper packaging…