When you unlock the 5th room in your homestead you will unlock a npc named the teller of secrets.
She will have 1 book for sale that gives +1 attribute point and 1 book for sale that gives you 3 ability points. These books cost 12,5k gold (before any bartering/attitude stuff applies) and will refresh on each level up of your highest experience character.
With kind regards,
Rashar.
