North York Central is not my local library by any means, but I did make the cross-town trek to check this behemoth out in all six floors of its glory.
Reminiscent of Bloor's Toronto Reference Library in design, I'd say NYCL is the cozy younger sibling. Also, unlike the Reference Library, a lot more of the books are actually for circulation. Each floor is divided according to field of interest, with whole stacks devoted solely to business, and another level to science. The very top floor is also worth a gander with its impressive collection of microfilms. If you're looking to study, I can vouch for the pin-drop noise level of the upper floors. Plenty of natural lighting and seating, as well as power outlets. The occasional coat trees dotting the perimeter were well made use of during my February visit.
Super convenient location for those commuting by TTC as it is in the same complex as North York Center Station. There is also a bustling food court if reading makes you peckish (I know it make me...but then again, I'm always up for a bite) and I believe food is allowed in the library's bottom floor study hall. Happy learning!