From the Beck Institute itself, here are five CBT Worksheets from Cognitive Therapy: Basics and Beyond, by Judith Beck. (They'll aim to sell you more on the site.) The book's mostly for therapists and the very, very curious, but take a look.
Psychotherapy worksheets of all kinds--depression, anxiety, anger management, stress reduction, self-esteem, groups, individuals, couples, adults, teens, children, CBT, DBT, ACT, PTSD, OCD, BPD...and more.