I like The Rand McNally College World Atlas . I've never found a thesaurus to fall in love with, but I suppose Roget's is the standard work. It's available to ALL Cornell students, not just freshmen. For complete information on this service, see the attached handout. The single best way to improve your own writing is by a steady diet of good reading.
Fine writing is lamentably scarce and getting scarcer, but it can still be found in a few places.
The Onion . Times Literary Supplement. Recent issues on newspaper shelves in Olin and Uris. New York Review of Book. Recent issues on newspaper shelves in Olin and Uris.