Aerenal Arcanist( Player's Guide to Eberron, p. 20)
Your family has studied wizardry for thousands of years. You spent your childhood in arcane libraries, and this early education gives you a great breadth of knowledge.
Elf, region of origin Aerenal,
You get a +2 bonus on Knowledge (arcana) checks. Every time you gain a wizard level after taking this feat (including 1st level), you can add one additional spell to your spellbook.