Oracle FAQ?

I have never used Oracle, or any other big relational database, before. My database experience ends at Q & A, MS-Works, and simple Unix DBM files. However, some of my clients are wanting things that will require a sophisticated database that can be set up to be easy to use for desk clerks, but powerful enough and configurable to meet individual clients' needs. Is Oracle something that can do this? If it is, is there an FAQ out there?

Also, does anyone out there have experience using Oracle for hotel/motel reservation systems? I would be very grateful for any feedback I could get. Thanks.

                                     --Jay Buie