Are you able to compile a GTK+ program from the command line?
Then, to compile:
int main( int argc, char **argv)
window = gtk_window_new(GTK_WINDOW_TOPLEVEL);
If it doesn't work, the packages you need for GTK2 are:
gcc -o hello hello.c `pkg-config --libs --cflags gtk+-2.0`
Obviously if you are working with GTK3, things are slightly different.
sudo apt-get install build-essential libgtk2.0-dev
If all that works, you can concentrate on the setup of the IDE, or other packages.