Basque is only spoken by about 700,000 people in the world, so there aren't a lot of resources available to help you learn it (unless you speak Spanish or French: since the Basque Country straddles the border of France and Spain there are more books on Basque in those languages). Colloquial Basque though is very good, better than most in the colloquial series of language packs (which are themselves generally above average), and although it won't take you all the way to complete fluency, it will teach you enough to get by, and enough to appreciate how fascinating Basque is. Alan King (who wrote the book with Begotxu Olaizola Elordi) also wrote another good book on Basque, called Basque: A Practical Introduction.