I would agree with jaihare that Reading Greek is a good place to start. We used it in college and there is a great focus on grammar and building basic vocabulary. If you know everything in the grammar book, you will have mastered the fundamentals of Attic grammar.
In some ways, Homeric Greek has a simpler grammar than Attic. For example, many of its forms are 'uncontracted', meaning that you can see the verb stem and the verb ending. Whereas in Attic these 'contract' to form new endings. However, the big obstacle in Homer is the vocabulary! There is a huge amount of vocab to learn! Some people claim that the vocab becomes easier because it is repeated, but this only applies if you are reading / learning the entire poem! Remember that the Iliad alone is 15,000 lines long.
We take the course in the following order:
1st year: Reading Greek and Prose Composition
2nd year: Homer (Iliad, Odyssey - excerpts), Herodotus (Histories - excerpts)
3rd year: Sophocles (Antigone), Euripides (Medea), Plato (Apology, Crito, Euthyphro)
Good luck with your study!