The book is available at Hathi Trust (I have not checked for other online sources). There's also a free audiobook at LibriVox.
Table of Contents
1. OF THE BIRTH OF KING ARTHUR
2. UTHER'S SON, RIGHTWISE KING OF ALL ENGLAND
3. HOW ARTHUR GAT HIS SWORD EXCALIBUR
4. BALIN AND BALAN
5. THE NOBLE ORDER OF THE ROUND TABLE
6. THE LADIES' KNIGHT
7. WISE MERLIN'S FOOLISHNESS
8. A STAG-HUNT AND WHAT CAME OF IT
9. THE TREACHERY OF MORGAN LE FAY
10. SIR LAUNCELOT OF THE LAKE
11. A NIGHT-TIME ADVENTURE OF SIR LAUNCELOT
12. HOW SIR LAUNCELOT CAME INTO THE CHAPEL PERILOUS
13. THE KNIGHT, THE LADY, AND THE FALCON
14. HOW A KITCHEN-PAGE CAME TO HONOUR
15. HOW SIR GARETH FOUGHT FOR THE LADY OF CASTLE PERILOUS
16. HOW SIR GARETH RETURNED TO THE COURT OF KING ARTHUR
17. HOW YOUNG TRISTRAM SAVED THE LIFE OF THE QUEEN OF LYONESSE
18. SIR TRISTRAM'S FIRST BATTLE
19. SIR TRISTRAM AND THE FAIR ISOUD
20. HOW SIR TRISTRAM DEMANDED THE FAIR ISOUD FOR KING MARK, AND HOW SIR TRISTRAM AND ISOUD DRANK THE LOVE POTION
21. HOW SIR TRISTRAM DEPARTED FROM TINTAGIL, AND WAS LONG IN THE FOREST
22. HOW KING MARK WAS SORRY FOR THE GOOD RENOWN OF SIR TRISTRAM
23. HOW SIR PERCIVALE OF GALIS SOUGHT AND FOUND SIR LAUNCELOT
24. OF THE COMING OF SIR GALAHAD
25. HOW THE QUEST OF THE HOLY GRAIL WAS BEGUN
26. HOW GALAHAD GAT HIM A SHIELD
27. SIR GALAHAD AT THE CASTLE OF MAIDENS
28. SIR LAUNCELOT'S REPENTANCE
29. SIR PERCIVALE'S TEMPTATION
30. THE VICTORY OF SIR BORS OVER HIMSELF
31. HOW SIR LAUNCELOT FOUND THE HOLY GRAIL
32. THE END OF THE QUEST
33. SIR LAUNCELOT AND THE FAIR MAID OF ASTOLAT
34. OF THE GREAT TOURNAMENT ON CANDLEMAS DAY
35. QUEEN GUENEVER'S MAY-DAY RIDE AND WHAT CAME OF IT
36. OF THE PLOT AGAINST SIR LAUNCELOT
37. HOW SIR LAUNCELOT DEPARTED FROM THE KING AND FROM JOYOUS GARD
38. HOW KING ARTHUR AND SIR GAWAINE INVADED SIR LAUNCELOT'S REALM
39. OF SIR MORDRED'S TREASON
40. OF ARTHUR'S LAST GREAT BATTLE IN THE WEST
41. OF THE PASSING OF KING ARTHUR
42. OF THE END OF THIS BOOK
