Dave Black has a list of his top ten books for studying New Testament Greek. He says:
For what it’s worth, I offer here a list of a few of my favorite books on New Testament Greek grammar. I hope this listing may stir some reader to an ambition to learn the language and learn it well. I fully realize that this catalog will be outdated as soon as it is published. I also exclude from it my own publications in the field, not because I believe them to be badly written, but because their author is hopelessly biased.
HT: Rod Decker