I have been looking for a way to group the psalms into topics that I can use as some sort of table of content when I need to quickly select a psalm to meditate and pray. I stumbled on a site called Creative Prayer that has done something similar, though a little rudimentary, and I decided to share the compilation here.  Christian Net has also made a similar effort.
The Psalms are prayers and songs written by king David and many other Jewish people based on Hebrew patterns of thought and poetry. The Psalms paint a picture of the complete range of human emotion and need and can serve as a tool for us to start or deepen our intimacy with God through prayer.  Many people throughout the centuries have found the psalms to be  an invaluable resource for prayer. We can choose a psalm that speaks to our prevailing needs and be sure that we can use it as a springboard into our own personal encounter with God.
Below is a list of all the Psalms and their topic.
The Book of Psalms
PSALM 1 – True Happiness in God’s Law
PSALM 2 – A Psalm for a Royal Coronation
PSALM 3 – Threatened but Trusting
PSALM 4 – Trust in God
PSALM 5 – Prayer for Divine Help
PSALM 6 – Prayer in Distress
PSALM 7 – God the Vindicator
PSALM 8 – Divine Majesty and Human Dignity
PSALM 9 – Thanksgiving for Victory and Prayer for Justice (A)
PSALM 10 – Thanksgiving for Victory and Prayer for Justice (B)
PSALM 11 – Confidence in the Presence of God
PSALM 12 – Prayer against Evil Tongues
PSALM 13 – Prayer in Time of Illness
PSALM 14 – A Lament over Widespread Corruption
PSALM 15 – The Righteous Israelite
PSALM 16 – God the Supreme Good
PSALM 17 – Prayer for Rescue from Persecutors
PSALM 18 – A King’s Thanksgiving for Victory
PSALM 19 – God’s Glory in the Heavens and in the Law
PSALM 20 – Prayer for the King in Time of War
PSALM 21 – Thanksgiving and Assurances for the King
PSALM 22 – The Prayer of an Innocent Person
PSALM 23 – The Lord, Shepherd and Host
PSALM 24 – The Glory of God in Procession to Zion
PSALM 25 – Confident Prayer for Forgiveness and Guidance
PSALM 26 – Prayer of Innocence
PSALM 27 – Trust in God
PSALM 28 – Petition and Thanksgiving
PSALM 29 – The Lord of Majesty Acclaimed as King of the World
PSALM 30 – Thanksgiving for Deliverance
PSALM 31 – Prayer in Distress and Thanksgiving for Escape
PSALM 32 – Remission of Sin
PSALM 33 – Praise of God’s Power and Providence
PSALM 34 – Thanksgiving to God Who Delivers the Just
PSALM 35 – Prayer for Help against Unjust Enemies
PSALM 36 – Human Wickedness and Divine Providence
PSALM 37 – The Fate of Sinners and the Reward of the Just
PSALM 38 – Prayer of an Afflicted Sinner
PSALM 39 – The Vanity of Life
PSALM 40 – Gratitude and Prayer for Help
PSALM 41 – Thanksgiving after Sickness
PSALM 42 – Longing for God’s Presence in the Temple (A)
PSALM 43 – Longing for God’s Presence in the Temple (B)
PSALM 44 – God’s Past Favor and Israel’s Present Need
PSALM 45 – Song for a Royal Wedding
PSALM 46 – God, the Protector of Zion
PSALM 47 – The Ruler of All the Nations
PSALM 48 – The Splendor of the Invincible City
PSALM 49 – Confidence in God Rather than in Riches
PSALM 50 – The Acceptable Sacrifice
PSALM 51 – The Miserere: Prayer of Repentance
PSALM 52 – The Deceitful Tongue
PSALM 53 – A Lament over Widespread Corruption
PSALM 54 – Confident Prayer in Great Peril
PSALM 55 – A Lament over Betrayal
PSALM 56 – Trust in God
PSALM 57 – Confidence Prayer for Deliverance
PSALM 58 – The Dethroning of Unjust Rulers
PSALM 59 – Complaint against Bloodthirsty Enemies
PSALM 60 – Lament after Defeat in Battle
PSALM 61 – Prayer of the King in Time of Danger
PSALM 62 – Trust in God Alone
PSALM 63 – Ardent Longing for God
PSALM 64 – Treacherous Conspirators Punished by God
PSALM 65 – Thanksgiving of God’s Blessings
PSALM 66 – Praise of God, Israel’s Deliverer
PSALM 67 – Harvest Thanks and Petition
PSALM 68 – The Exodus and Conquest, Pledge of Future Help
PSALM 69 – A Cry of Anguish in Great Distress
PSALM 70 – Prayer for Divine Help
PSALM 71 – Prayer in Time of Old Age
PSALM 72 – A Prayer for the King
PSALM 73 – The Trial of the Just
PSALM 74 – Prayer at the Destruction of the Temple
PSALM 75 – God the Judge of the World
PSALM 76 – God Defends Zion
PSALM 77 – Confidence in God during National Distress
PSALM 78 – A New Beginning in Zion and David
PSALM 79 – A Prayer for Jerusalem
PSALM 80 – Prayer to Restore God’s Vineyard
PSALM 81 – An Admonition to Fidelity
PSALM 82 – The Downfall of Unjust Gods
PSALM 83 – Prayer against a Hostile Alliance
PSALM 84 – Prayer of a Pilgrim to Jerusalem
PSALM 85 – Prayer for Divine Favor
PSALM 86 – Prayer in Time of Distress
PSALM 87 – Zion the True Birthplace of Diaspora Pilgrims
PSALM 88 – A Despairing Lament
PSALM 89 – A Lament over God’s Promise to David
PSALM 90 – God’s Eternity and Human Frailty
PSALM 91 – Security under God’s Protection
PSALM 92 – A Hymn of Thanksgiving for God’s Fidelity
PSALM 93 – God is a Mighty King
PSALM 94 – A Prayer for Deliverance from the Wicked
PSALM 95 – A Call to Praise and Obedience
PSALM 96 – God of the Universe
PSALM 97 – The Divine Ruler of All
PSALM 98 – The Coming of God
PSALM 99 – The Holy King
PSALM 100 – Communal Thanks in the Temple
PSALM 101 – Norm of Life for Rulers
PSALM 102 – Prayer in Time of Distress
PSALM 103 – Praise of Divine Goodness
PSALM 104 – Praise of God the Creator
PSALM 105 – God’s Fidelity to the Promise
PSALM 106 – Israel’s Confession of Sin
PSALM 107 – God the Savior of Those in Distress
PSALM 108 – Prayer for Victory
PSALM 109 – Prayer of a Person Falsely Accused
PSALM 110 – God Appoints the King both King and Priest
PSALM 111 – Praise of God for Goodness to Israel
PSALM 112 – The Blessings of the Just
PSALM 113 – Praise of God’s Care of the Poor
PSALM 114 – The Lord’s Wonders at the Exodus
PSALM 115 – The Greatness of the True God
PSALM 116 – Thanksgiving to God Who Saves from Death
PSALM 117 – The Nations Called to Praise
PSALM 118 – Hymn of Thanksgiving
PSALM 119 – A Prayer to God, the Lawgiver
PSALM 120 – Prayer of a Returned Exile
PSALM 121 – The Lord My Guardian
PSALM 122 – A Pilgrim’s Prayer for Jerusalem
PSALM 123 – Reliance on the Lord
PSALM 124 – God, the Rescuer of the People
PSALM 125 – Israel’s Protector
PSALM 126 – The Reversal of Zion’s Fortunes
PSALM 127 – The Need of God’s Blessing
PSALM 128 – The Happy Home of the Just
PSALM 129 – Against Israel’s Enemies
PSALM 130 – Prayer for Pardon and Mercy
PSALM 131 – Humble Trust in God
PSALM 132 – The Covenant between David and God
PSALM 133 – A Vision of a Blessed Community
PSALM 134 – Exhortation to the Night Watch to Bless God
PSALM 135 – Praise of God, the Ruler and Benefactor of Israel
PSALM 136 – Hymn of Thanksgiving for God’s Everlasting Love
PSALM 137 – Sorrow and Hope in Exile
PSALM 138 – Hymn of a Grateful Heart
PSALM 139 – The All-knowing and Ever-lasting God
PSALM 140 – Prayer for Deliverance from the Wicked
PSALM 141 – Prayer for Deliverance from the Wicked
PSALM 142 – A Prayer in Time of Trouble
PSALM 143 – A Prayer in Distress
PSALM 144 – A Prayer for Victory and Prosperity
PSALM 145 – The Greatness and Goodness of God
PSALM 146 – Trust in God the Creator and Redeemer
PSALM 147 – God’s Word Restores Jerusalem
PSALM 148 – All Creation Summoned to Praise
PSALM 149 – Praise God with Song and Sword
PSALM 50 – Final Doxology
