Intermediate-advanced spanish grammar learning resources

[jasee]

Hi, I'd like to continue with my education on spanish grammar, but i'm a little confused with what i should study next. I finished the book spanish grammar for dummies, which covers the verb form and tenses etc, like most of the books i've looked through, but I don't know where to go at this point. I'd really like to understand comprehensively how to speak spanish, so if anyone can tell me what books will help me complete my grammar learning, or web sites, or more specifically, what topics i should still learn, please help me out. Thank you..