Go to All Music (allmusic.com).
Click on "Moods" in the "site menu" at the top right of the screen.
Click on a mood that matches the personality trait of the person in mind. For example, you could click on "aggressive" or "joyous."
Click on "Click here for full list" under "Songs."
Choose a song from the "Significant Songs" list. For example, in the "Calm/Peaceful" list, you would find songs like Ella Fitzgerald's "Black Coffee" and the Association's "Cherish."
Preview the song at a streaming music service such as Grooveshark (grooveshark.com) or Last.fm.