I'm not too familiar with the process myself as I'm still learning, but I've picked out a few links from the wiki that I believe should put you on the right path:

http://wiki.maemo.org/Documentation/...eveloper_Guide
Specifically the GNU Build System section in reference to makefiles.

http://wiki.maemo.org/Desktop_file_format
Details the contents and placement of .desktop files.

http://wiki.maemo.org/Documentation/...d_Distributing
and
http://wiki.maemo.org/User:Jebba/Package_Building_HOWTO
Helped me out a great deal regarding packaging.