My husband is a Spanish teacher/interpreter and he recommends the Practice Makes Perfect Spanish Verb Tenses by Dorothy Richmond. I have been using it and if I had studied like I was supposed to, I would have been speaking advanced Spanish within 6 months to a year using that book. I also use another book that works on vocabulary and using the language in every day scenarios: Spanish Now by Barron's. It really mixes up the vocabulary and gives you reading exercises and questions/answers activities. There is a large vocabulary unit at the back to do extra practice with as well. Plus, you have to start conversing right away. If it is all books, it will be difficult later to get communicating. Also, to get the syntax of the language it is very useful to read in Spanish for at least 15 minutes a day, but don't worry if you understand it or not. You will be able to pick out words here and there as you learn. Enjoy!