What books of the Bible were written to the Greeks? I am interested in reading those books at this time.
The New Testament
The entire New Testament, with the possible exception of the Gospel of Matthew, was originally written in Greek, and intended to address a Greek-speaking audience. Of course, the entire Mediterranean world used Greek as a learned language and a language of international communication at the time. Some of the books do seem to be more aimed at Greek-speaking Jews than at non-Jews. (Also, the writers seem to use the word “Greeks” as a general synonym for “non-Jews” quite a bit.)
So you could say that the entire New Testament counts for the purpose of your question, as it was all addressed to Greek-speakers.
However, certain books seem to be more specifically directed to non-Jews. These would include the Gospel of Luke, the Pauline Epistles, and perhaps the Acts of the Apostles. These do not assume familiarity with the Jewish Bible the way some other books (particularly the Gospel of Matthew) do.
If you specifically meant Greeks, as opposed to non-Jews in general, then you want Paul’s letters to
- The Galatians — Galatia is in modern-day Turkey, but was regarded as Greek at the time,
- The Ephesians — Ephasus is also in modern-day Turkey,
- The Philippians — Phillipi was a city on the Greek island Thasos,
- The Colossians — Collossae is also in modern-day Turkey,
- The Thessalonains (two letters) — Thessaloniki is definitely a Greek city.
The Old Testament
The Jewish Bible was written predominantly in Hebrew, with some small sections in Aramaic. These books were later translated into Greek, for the benefit of Greek-speaking Jews, in a collection known as The Septuagint. This actually included some books originally written in Greek, which were omitted from the Jewish Bible when it was finalized.
The Eastern Orthodox Church takes the Septuagint as the basis for their Old Testament to this day. The Catholic Church takes its Old Testament from the Jewish Bible, but also takes the books found in the Septuagint, which it terms Deuterocanonical. Protestant churches in general simply take the Jewish Bible as their Old Testament, and either completely ignore the Deuterocanon or term it Apocrypha, which they deem interesting and potentially useful reading, but not part of the Bible proper.
The Catholic Deuterocanon was written for Hellenized Jews, who may or may not count as “Greeks” for the purpose of your question.
It's a little hard to tell what you're asking since as it was pointed out in the comments "Greek" in the Gospel usage as "neither Greek nor Jew". Which were the folks St. Paul set out to convert, much to St. Peter's initial chagrin.
So I think you're wanting to read most of the Pauline Epistles
All of which (Except Hebrews and Romans) are addressed to early Christian communities, leaders or friends in Greece.
So, get that Big Book off the coffee table, crack it about 5/6ths of the way open and start reading, you won't regret it.
If you're asking a completely different question, about the language, the entire Old Testament (which is in the Catholic Bibles and more so in Orthodox Bibles) was written in Greek before it was translated into Latin by St. Jerome. This is the Septuagint Bible, Septuagint meaning 70 Books. The New Testament is all in Greek. If you want to read the Greek, with the Latin and English translations side-by-side, there's a good Bible at NewAdvent.org that even I can make sense of and I know Big-Omega Greek (except Kyrie, Christi and Eleison )