Cisco Press is offering a big discounts on books for the new year as well as a chance to win a free exam voucher. You can save up to 70% on books, videos, and other training material by checking out this website. Not sure which certification to work on? I'm personally working on ACI related training, but all levels of the DataCenter training are really helpful right now, too.
I highly recommend making use of this offer as training materials get expensive! Plus the new year is the perfect time to start studying for a new certification or just read more about the tech in which you're interested.