Juan Kattan-Ibarra

“This is a complete course in understanding, speaking and writing Latin American Spanish. If you have never learnt Spanish, or want to improve on existing skills and apply them to Latin America for holiday or business travel, than Teach yourself Latin American Spanish is for you.” - Cover.
The course contains a series of graded units, including dialogues, grammar explanations and a wide variety of exercises.

One of the main reasons I like this book is that it devotes a lot of space to functions. For example, what language do you use to invite someone to do something, express sympathy, or ask advice? That kind of information is not easily found in other books, because it's not grammar, strictly speaking, but half of this book addresses it. A good addition to your shelf of Spanish language reference books.