There you also have the possibility to browse the code online without having to download everything.
It can be accessed using GIT...
...or using SVN:
svn checkout github.com/nschlia/libdvdetect/ libdvdetect-code
That will make it much easier to get a working binary of the library for Windows. Together with a big set of other useful libraries, and even Qt, it can be built using MXE (M cross environment).
"MXE (M cross environment) is a Makefile that compiles a cross compiler and cross compiles many free libraries such as SDL and Qt."