Congratulations!
Your employer should provide you with the tools you would need to do your day to day job. I have never had an employer that did not provide at the very least annual books. Even 1 denied claim is worth the cost of annual books. If I had to pay out of my own pocket for books, I would probably not buy EVERY year, but make sure I carefully reviewed the annual changes and note them in last year's book. Depending on your responsibilities, and number of employees doing specific responsibilities, your employer may or may not purchase books for each employee.
Most employers will also have a subscription to some type of online coding tool - Supercoder, SpeedECoder, AAPC Coder, EncoderPro, etc. Those online sites usually have tools to look up LCDs/NCDs, CCI edits, global days, etc. Generally, each offers different levels of subscriptions, with additional tools for the more expensive options.
If you get a job in a specialty, there are often books dedicated to common specialties that could be helpful. I work in gynecologic oncology (which is a very specialized subspecialty) and rarely find the general ob/gyn books to be much help, so I don't bother.