The effort of reconstructing Proto-IE has been going on for over 200 years now, and more than just a handful of words have been reconstructed; in fact, in the 19th century scholars thought they could write a whole story in PIE (nobody is that optimistic anymore). In 1959, Julius Pokorny published the "Indogermanisches Etymologisches Wörterbuch", in 3 volumes -- but although this is an important work, and still being cited in modern works, it was already way out of date when it was published, because Pokorny decided to ignore that the decipherment of the Anatolian languages (Hittite and Luvian) had proven that Saussure's ingenious speculation about laryngeal consonants in PIE was correct.

"8000 years" is a bit long; if, as seems likely on linguistic, archeological and genomic evidence, the speakers of PIE were identical with the people of the Yamnaya culture in the Pontic steppe, 6000 years seems to be a better estimate.

What's so important about Fabius Pictor? Most of the stuff he collected was fictional, anyway (the oral traditions of the noble families of his day), and is the basis for the early parts of Livy's history.