Look for impressionist music. It's still tonal and doesn't worry about these annoying harmony rules. Check out Ravel's works and you see tons and tons of unresolved 7th chords, 9th chords etc. Debussy (and Respighi) are also good to listen to^^
Here's a nice place to understand more features of impressionistic music: http://academic.udayton.edu/PhillipMagnuson/soundpatterns/microcosms/impressionism.html
Hope this helped somehow