Genesis Rabbah 9:8: Behold, 'it was very good' refers to the dispensation of happiness.

Psalms 119:1: Happy are the simple of heart who follow G-d's way.

Psalms 4:8: Thou hast put gladness in my heart.

Ethics of the Fathers 4:1: Who is rich?  One who is happy with his portion.

Deuteronomy 16:16: And you will be completely joyous.

Mivchar Hapanenim, 400: He is the greatest of men whose mind is most tranquil and whose association with others is most happy.

Isaiah 49:13: Tell the heavens and earth to celebrate and sing!  Command every mountain to join in song!

Sefer Ma'alot Hammidot: If one has an obliging mind, his life is good, his joy is constant, and is not bowed down by adversity.

Psalm 112:1,3: Happiness is the mane who fears G-d and who is ardently devoted to G-d's commandments.  Wealth and riches are in his house, and his beneficence lasts forever.

Midrash Tanchuma Exodus 27: The heart that rejoices over his brother's rise to greatness will come and rejoice and wear the Urim v'Tumim.

Proverbs 15:13: A merry heart makes a cheerful face, but by sorrow of the heart the spirit is broken.

Ethics of the Fathers 1:15: Say little and so much, and receive all men with a cheerful face.

Ethics of the Fathers 3:16: ...receive every person cheerfully.

Ethics of the Fathers 4:20: Initiate a greeting to every person...

Tan'anit 29a: When Adar arrives we increase our joy.

Menucha V'Simcha Zemer: Contentment and gladness and light - for the Jews on this day of Sabbath, day of delights.

Psalm 69:32: The humble will see it and be glad.

Psalm 126:2: Then our mouth will be filled with laughter and our tongue with glad song.

Kol Mekasesh Zemer: this is the day Hashem has made; let us rejoice and be glad with it.

Sheva Brachot Blessings: Blessed are You, Hashem, Who gladdens groom and bride.

Psalm 92:5: I sing out joyously about the deeds of Your hands.

Joel 2:23: Be glad the, ye children of Zion, and rejoice...

Deuteronomy 16:14-15: And thou shalt rejoice...and thou shalt be altogether joyful.

Ecclesiastes 11:9: Rejoice, young man, in your youth, and let your heart cheer you in the days of your youth, follow the ways of your heart and the sight of your eyes.

Ecclesiastes 8:15: I extol the concept of rejoicing for there is nothing better for man under the sun.

Shir Ha'Yichud: To serve with joy and a good heart...

Ma Yedidut Zemer: Six days you shall labor, and on the seventh let us rejoice.