Douglas Adams
1. 
The Hitchhiker’s Guide to the Galaxy (Hitchhiker's Guide to the Galaxy, #1)
by:
Douglas Adams
4.22 avg rating — 1,969,975 ratings 2. 
The Restaurant at the End of the Universe (The Hitchhiker's Guide to the Galaxy, #2)
by:
Douglas Adams
4.20 avg rating — 309,582 ratings 3. 
Life, the Universe and Everything (The Hitchhiker's Guide to the Galaxy, #3)
by:
Douglas Adams
4.16 avg rating — 246,197 ratings 4. 
So Long, and Thanks for All the Fish (Hitchhiker's Guide to the Galaxy, #4)
by:
Douglas Adams
4.09 avg rating — 182,141 ratings 5. 
Dirk Gently's Holistic Detective Agency (Dirk Gently, #1)
by:
Douglas Adams
3.97 avg rating — 146,635 ratings 6. 
The Long Dark Tea-Time of the Soul (Dirk Gently, #2)
by:
Douglas Adams
4.04 avg rating — 88,594 ratings 7. 
Mostly Harmless (The Hitchhiker's Guide to the Galaxy, #5)
by:
Douglas Adams
3.96 avg rating — 136,953 ratings 8. 
The Ultimate Hitchhiker's Guide: Five Complete Novels and One Story (Hitchhiker's Guide to the Galaxy, #1-5)
by:
Douglas Adams
4.38 avg rating — 334,638 ratings 
10. 
The Salmon of Doubt: Hitchhiking the Galaxy One Last Time
by:
Douglas Adams
3.94 avg rating — 30,517 ratings 11. 
And Another Thing... (The Hitchhiker's Guide to the Galaxy, #6)
by:
Eoin Colfer
3.57 avg rating — 33,086 ratings 
13. 
Wish You Were Here: The Official Biography of Douglas Adams
by:
Nick Webb
4.14 avg rating — 2,895 ratings 
15. 
Parley After Life - DIY Guide to Death and other Taxes
by:
Robby Miller
3.35 avg rating — 17 ratings 16. 
The More Than Complete Hitchhiker's Guide (Hitchhiker's Guide, #1-4 + short story)
by:
Douglas Adams
4.58 avg rating — 3,734 ratings 17. 
The Hitchhiker's Guide to the Hitchhiker's Guide to the Galaxy
by:
Eoin Colfer
3.93 avg rating — 30 ratings 18. 
A Completely and Utterly Unauthorized Guide to Hitchhiker's Guide
by:
M.J. Simpson
3.76 avg rating — 45 ratings 19. 
The Rough Guide to The Hitchhiker's Guide to the Galaxy
by:
Marcus O'Dair
3.81 avg rating — 36 ratings 
22. 
The Deeper Meaning of Liff: A Dictionary of Things There Aren't Any Words for Yet--But There Ought to Be
by:
Douglas Adams
3.94 avg rating — 4,794 ratings 23. 
Don't Panic: Douglas Adams & The Hitchhiker's Guide to the Galaxy
by:
Neil Gaiman
4.28 avg rating — 25,283 ratings 
25. 
26. 
The Science of the Hitchhiker's Guide to the Galaxy
by:
Michael Hanlon
3.60 avg rating — 235 ratings 27. 
The Illustrated Hitchhiker's Guide to the Galaxy
by:
Douglas Adams
4.22 avg rating — 1,969,975 ratings 28. 
Hitchhiker's Guide To The Galaxy: The Filming of the Douglas Adams classic
by:
Robbie Stamp
4.41 avg rating — 3,048 ratings