How long did it take to collect all of the writings that eventually formed the first version of the Bible? In other words, starting with when the first writing was created (I'll say when it was completed rather than started) to when it was first printed/published/etc., how long did it take?
Much of when the Old Testament was written is purely conjecture, but many modern scholars believe that it was written some time in the period when the Persians captured Babylon in 538 BC. Others believe Moses authored the Pentateuch, which is Genesis - Deuteronomy, which would mean that these books were authored some time around 1300 - 1500 BC.
There is also some conjecture that Job is the earliest written account in the Bible, and would predate Moses' writings, although those who hold this theory do not believe that the actual writing of the Book of Job predates the writing of the Pentateuch by much, even though they believe that the actual account of Job happened long before, and many believe Job lived before the flood.
The last book of the New Testament is believed to have been Revelations, written in approximately 68 AD, but yet others believe that this book was written around 95 AD.
We don't know exactly when the books of the Bible were written, but we can, through cross-referencing external sources, determine when the historical figures in the Bible lived. Either way, the common consensus is that the writing of the books of the Bible began some time after 1500 BC, and concluded prior to 100 AD. This would be a period of about 1600 years.
The first known "canonization" of the Scripture was proposed by Marcion of Sinope around 140 AD. Since then there have been multiple canons of Scripture proposed, with different ones accepted by various groups, containing anywhere from 66-81 books. Currently, the typical Protestant Bible is a 66 book canon, from the 4th century synod which listed 39 books of the Old Testament. The typical Catholic Bible has 73 or 74 books, from the 4th century synod which listed 46 books of the Old Testament (5 books were merged into other books in this list, making a total of 51 books), and some Catholic Bibles also contain 2 Esdras. Both the Protestant and the Catholic New Testaments are the same 27 books.
The earliest Hebrew scripts (which were the written form of a long, long oral tradition) that eventually became the torah (the first five books of the bible) were written around 900BC, and the Tenakh (the earliest Hebrew bible) was compiled around 400BC.
The New Testament was fully written by 150 AD and after much discussion was fully compiled between 500 - 600 AD.
The old testament and the new testament together were probably written and compiled over a span of 1600 years.
The Bible I read (King James Version) Took about 3000 years from start to finish. But you asked about:
The first version of which Bible? The Roman Catholic Bible? The Greek Orthodox Bible? The Protestant Bible? The word "Bible" is loosely translated "The Books." There have been many Bible translations and revisions to canon. Some books—like the Apocrypha—have been added and removed from canon multiple times over the ages. The first Christian Bible was the Catholic Vulgate, translated by St. Jerome from the best Hebrew, Greek and Aramaic codices available at the end of the fourth century including the Vetus Latina Codex and the Codex Gigas. The Vulgate was "The Bible" for about 1000 years until the Protestant movement, when several English versions of the Vulgate were translated like the Douay-Rheims Bible, while others re-opened the original codex to make an English translation.
I think a proper answer would take too long, so I'm instead going to leave you with a list of significant events that contributed to the evolution of the Bible Canon. Hopefully this will give you a starting point to learn how the Bible canon changed and evolved over the centuries.