I was told by a co-worker that there is an hourly charge for using Creative Cloud, in addition to buying the year's membership. Is that the case? If yes, what is the hourly cost?
No hourly charge that I'm aware of, Creative Cloud Membership is a kind of subscription to products with some additional services, you can get a year long or monthly subscription. You pay monthly with both though.
These links talk about what it is and how it works