Since you've asked for rare spells, and it is too much of a hassle to properly format a PM to you with all this information, here is a short section on rare spells that some more advanced spell casters may be familiar with (attached file).

And here is a little section on high magic for elves. Not all of it would apply to Irenicus, but some of them may be appropriate.

the seven sisters pdf did not work for me. the High elf did tho.

I've re-uploaded the seven sisters spells.pdf. Hopefully it will work now.

As well, I've also got a selection of Zhentil keep spells that Cyricists, Bane worshipers, and other nasties like to use.

And here's one on Halruaa spells. Their spells are similar to many of the Old Empires Spells, since Halruaa was once part of that empire grouping IIRC.

And here is a small selection of Myth Drannor spells

Thank you for posting all that information; I will find them incredibly useful for some of the liches and such.

-Galactygon

And another couple, some of these are monster only spells, but the text included should explain that better than I could. These are Phaerimm (the creatures that had a large role in the destruction of Netheril) spells.

And another one on Alhoon and their spells (Illithid Liches, there are a couple in BGII).

The Magister contains a variety of rarer spells that most in the realms will be unfamiliar with.

For any having a hard time opening the Seven Sisters Spells I posted above, you can try this re-encoded one here. The quality is lower, and the file size is slightly larger, but it may work for you.

A little selection of Drow Spells. Some of these will be familiar.