Spanish Reference Books

Harrap's Concise Spanish Dictionary, $17.00, hardcover.
The paperback version of this is the best portable dictionary to be found: it gives extensive idiomatic examples of the use of both Spanish for English speakers and English for Spanish speakers, has verb and pronunciation charts, and is small enough to carry to class or travelling. It's never let me down, unlike other pocket-sized dictionaries. While this one is pocket-book sized, it's nearly half as thick as it is wide! It is also, at $4.79 the most reasonably priced dictionary on the market. The hardcover here is a 1997 revised edition and hopefully they will soon be coming out with another paperback. Until then, I'd recommend this Harrap's Concise Hardcover as a reasonable choice for a desktop dictionary. It really has a great selection of contemporary idiomatic usages and, very important, the prepositions that accompany verbs in different applications.
Since the Paperback Harrap's Concise Dictionary, at $4.79, is currently out of print, a substitute, from the same publisher, at the same price, is Harrap's Giant Paperback Spanish Dictionary. While it has nowhere near the number of wonderful idiomatic usages, it is still a moderately priced paperback and, as paperback dictionaries go, more complete than most.
The Usborne Beginner's Spanish Dictionary, $10.36
A picture dictionary, humorously illustrated for adults, with useful vocabulary--both nouns and verbs--arranged thematically
501 Spanish Verbs, Fully Conjugated in All the Tenses, $11.16
Alphabetically arranged pages display the verbs conjugated in all tenses, with usage examples and idioms at the bottom of the page. A great book for reference or just browsing.
Mierda Y Mas Mierda. the Spanish you weren't taught in school:
Mierda! The Real Spanish You Were Never Taught in School, F. de Talavera Berger, $7.16
Más Mierda!, F. de Talavera Berger, $6.36
In Few Words/En Pocas Palabras: A Compendium of Latino Folk Wit and Wisdom, José Antonio
Burciaga, $11.96
Books I've seen recommended:
Diccionario Planeta, $39.95 (Hardcover)
New Reference Grammar of Modern Spanish, John Butt & Carmine Benjamin, (2nd edition), $23.96
The first edition is what I've seen recommended, but am listing this one in its stead.