To find travel literature, use the phrase "description and travel" in your search. For example, do a subject search for "india description and travel" or "south africa description and travel" to retrieve accounts of travel in those countries.
You may also find it useful to use the "set limits" option in the Main Catalog to limit your search to works published in a particular time and place. For example, to find works about India published in England in the early 19th century, you can limit your results to works published in England between 1800 and 1840, then do a keyword search for "india."
The Hakluyt Society publishes editions and translations of travel accounts. In Firestone, they can be found on B floor at G161.H2.
A complete list is available at http://www.hakluyt.com/hak-soc-bibliography.htm
A list of out-of-copyright volumes available online through Google Books is at http://www.hakluyt.com/digital_books.htm
The Empire Writes Back
Part I Indian views on Britain and Empire, 1810-1915, from the British Library, London [microform] MICROFILM 11849 http://www.adam-matthew-publications.co.uk/digital_guides/empire_writes_back_part_1/Contents-of-Reels.aspx
Part II Black and Asian visitors to Britain, 1734-1942, from the British Library, London [microform] MICROFILM 12021 http://www.adam-matthew-publications.co.uk/digital_guides/empire_writes_back_part_2/Contents-of-Reels.aspx
"Broadway Travellers" was a series of translations of classic travel texts from before 1800 issued in the 1920s and 1930s.
Medieval Travel Writing
Digital edition of manuscripts of some of the most important works of European travel writing from the later medieval period.
Travel Writing, Spectacle and World History
Brings together hundreds of accounts by women of their travels across the globe from the early 19th century to the late 20th century.
There are several useful volumes in the Gale Dictionary of Literary Biography series. Although you can consult the series online, it is sometimes easier to use the print versions:
British travel writers, 1940-1997. RECAP PN451 .D53 v.204
British travel writers, 1910-1939. RECAP PN451.D53 V.195
British travel writers, 1876-1909. RECAP PN451 .D53 v.174
British travel writers, 1837-1875. RECAP PN451.D53 v.166
American travel writers, 1850-1915. RECAP PN451.D53 v.189
American travel writers, 1776-1864. RECAP PN451.D53 v.183