(Note made by Isabelle: later translations are usually more accessible. I AM not a fan of Jowett. Since she composed this list I thought it necessary to add this)
Early Works:
Apology
Crito
Euthyphro (holiness, the Euthyphro dilemma)
Ion
Laches (courage)
Protagoras (the teachability of virtue)
Gorgias (rethoric vs. philosophy)
Meno (virtue, Meno's paradox)
Middle Works
Parmenides - Forms
Phaedo (the death of socrates, the afterlife)
Phaedrus (love and rethoric)
Republic (politics, the state and the soul)
Symposium (true love, the 'Ladder of Love')
Theaetetus (knowledge)
Later Works
Critias (Atlantis=
Sophist (more on Forms)
Timaeus (the purpose of the universe)
On Aristotle
David M.Balme - Aristotle on Nature and Living Things: Philosophical and Historical Studies
Cristopher Shields - Aristotle
David Furley - From Aristotle to Augustine
By Aristotle
(Another note by Isabelle: Oxford translations are best)
The Nicomachean Ethics (virtue ethics, leads into Politics)
Rethoric
Metaphysics
Poetics
Politics
Cynicism
Farrand Sayre - Diogenes of Sinope: A study of Greek cynicism
R. Bracht Branham, Marie-Odile Goulet-Cazé -The Cynics: The Cynic Movement in Antiquity and Its Legacy
Epicureanism
James Warren - The Cambridge's companion to Epicureanism
Eugene O'connor - The essential Epicurus
Lucretius - The nature of things
Stoicism
(Isabella specified Penguin Classics)
Seneca - Letters from a stoic
Epictetus - Discourses and selected writings
Marcus Aurelius - Meditations
Skepticism
Norman Maccoll - The Greek Sceptics: From Pyrrho to Sextus
Sextus Empiricus - Outlines of Pyrrhonism
Richard T. Wallis - Neoplatonism and Gnosticism
John Gregory - The neoplatonists
Plotinus - The enneads
Travel Literature
General
From the Meadows of Gold by Mas'udi
The Travels of Ibn Battutah
Voyages and Discoveries by Richard Hakluyt
The Journals of Captain James Cook
South: The Endurance Expedition by Ernest Shackleton
The Last Grain Race by Eric Newby
Collected Travel Writing by Evelyn Waugh
Travels With Herodotus by Ryszard Kapuscinsk
The Way of the World by Nicolas Bouvier
Pecked to Death by Ducks by Tim Cahill
Yoga For People Who Can't Be Bothered to Do It by Geoff Dyer
Europe
Guide to Greece by Pausanias
Ibn Fadlan and the Land of Darkness by Ibn Fadlan
A Journey to the Western Islands of Scotland by Samuel Johnson
A Sentimental Journey by Laurence Sterne
Letters From England by Voltaire
Italian Journey: 1786-1788 by Johann Wolfgang von Goethe
Travel Pictures by Heinrich Heine
Letters from Russia by Adolphe De Custine
Winter Notes on Summer Impressions by Fyodor Dostoevsky
Sakhalin Island by Anton Chekhov
The Innocents Abroad by Mark Twain
D. H. Lawrence and Italy by D.H. Lawrence
Black Lamb and Grey Falcon by Rebecca West
Mani: Travels in the Southern Peloponnese by Patrick Leigh Fermor
A Time of Gifts by Patrick Leigh Fermor
The Silent Traveler in London by Chiang Lee
Stones of Aran: Labyrinth by Tim Robinson
The Colossus of Maroussi by Henry Miller
Trieste And The Meaning Of Nowhere by Jan Morris
In Siberia by Colin Thubron
The Rings of Saturn by W. G. Sebald
Fado by Andrzej Stasiuk
Asia
The Travels of Marco Polo
The Travels of Sir John Mandeville
An Ottoman Traveller: Selections from the Book of Travels of Evliya Celebi
Narrow Road to the Deep North and Other Travel Sketches by Matsuo Basho
Unbeaten Tracks in Japan by Isabella L. Bird
The Malay Archipelago by Alfred Russel Wallace
A Secret Pilgrimage to Mecca and Medina by Richard Burton
Glimpses of Unfamiliar Japan by Lafcadio Hearn
The Southern Gates of Arabia by Freya Stark
A Time to Keep Silence by Patrick Leigh Fermor
A Barbarian in Asia by Henri Michaux
Peking Story: The Last Days of Old China by David Kidd
Hindoo Holiday by J.R. Ackerley
Seven Years in Tibet by Heinrich Harrer
A Short Walk in the Hindu Kush by Eric Newby
The Inland Sea by Donald Richie
Arabian Sands by Wilfred Thesiger
The Lost Heart of Asia by Colin Thubron
The Snow Leopard by Peter Matthiessen
Riding the Iron Rooster by Paul Theroux
The Great Railway Bazaar by Paul Theroux
City of Djinns by William Dalrymple
Their Heads Are Green and Their Hands Are Blue by Paul Bowles
Africa
Travels in the Interior of Africa by Mungo Park
Travels in West Africa by Mary Kingsley
Source of the Nile by Richard Burton
The Naturalist on the River Amazons by Henry Walter Bates
Travels in the Congo by Andre Gide
Out of Africa by Isak Dinesen
Green Hills of Africa by Ernest Hemingway
Journey Without Maps by Graham Greene
The Voices of Marrakesh by Elias Canetti
North of South by Shiva Naipaul
African Laughter by Doris Lessing
The Americas
Chronicle of the Narvaez Expedition by Alvar Nunez Cabeza De Vaca
Personal Narrative of Travels to the Equinoctial Regions of America by Alexander von Humboldt
History of a Voyage to the Land of Brazil by Jean de Lery
The Journals of Lewis and Clark
The Oregon Trail by Francis Parkman
American Notes for General Circulation by Charles Dickens
A Week on the Concord and Merrimack Rivers by Henry David Thoreau
Travels in Alaska by John Muir
Roughing It by Mark Twain
Two Years in the French West Indies by Lafcadio Hearn
Kabloona by Gontran de Poncins
Here is New York by E.B. White
Travels With Charley: In Search of America by John Steinbeck
Kon-Tiki by Thor Keyerdahl
The Lawless Roads by Graham Greene
In Patagonia by Bruce Chatwin
An African in Greenland by Tété-Michel Kpomassie
I See by My Outfit by Peter S. Beagle
Coming into the Country by John McPhee
Into the Wild by Bill Bryson
A Turn in the South by V.S. Naipaul
The Old Patagonian Express by Paul Theroux
Anthologies
A Book of Traveller's Tales by Eric Newby
Travel Writing 1700-1830
Colonial American Travel Narratives
Travels in the Reich, 1933-1945: Foreign Authors Report from Germany
Other Routes: 1500 Years of African and Asian Travel Writing
Unsuitable for Ladies: An Anthology of Women Travellers