Crochet Funky Mukluks Boots by PattyLaBell on Etsy, €4.50/US dollars $6.00.
Crochet Dreamz: Brooklyn Boot Cuffs, Free Crochet Pattern
A Peek of Cozy: Boot Cuff Pattern
Love2bloom: A Peek of Cozy: Boot Cuff Pattern
#11 Cut part of the arm off of an old sweater to make boot warmers! ~ 31 Clothing Tips Every Girl Should Know
31 Clothing Tips & Tricks Every Girl Should Know (With Pictures)
Ravelry: Boot Cuffs by LBK63 pattern by Lori Bennett Kramer
The Patterns Keep Coming! - ELK Studio - Handcrafted Crochet Designs
Crochet Boot Cuffs – Free Pattern — Compulsive Craftiness
Ball Hank n' Skein: Knee-High Boot Socks! I've seen pictures of these before but here is the actual pattern (free) and tips on getting the fit right.