The boxed set Netheril: Empire of Magic also contains the sourcebook The Winds of Netheril. On pages 26-28, Table 9 lists the year in which almost any AD&D spell has been introduced in Netheril. And the table on pages 23-25 lists the original names of the spells.
For example, consider Polymorph Self. On page 24, we read that its original name was Quantoul's selfmorph. And on page 26, we see that Quantoul's selfmorph was introduced in 1838 NY (-2021 DR).
Having said this, it is worth noting that by the time Netherese arcanists introduced these spells, it is likely that the elves might have already had access to some. Quoting from the boxed set Cormanthyr: Empire of the Elves (page 124):
... the bulk of the races on Toril tapped only the magics granted by their own gods via shamanistic and priestly magics. For many centuries, only the dragons and the elves tapped into the Weave without divine measure.
Finally, we know that the Nether Scrolls, whose discovery by the humans greatly boosted their understanding of magic, were written by the sarrukh circa -30000 DR. However, these scrolls describe fundamental magical theory, so the Netherese arcanists had to develop the spells themselves.