Oracle...

Well I was looking through the manual, and for someone who doesn't know much about databases or working with them, it wasn't too clear.... So my question is: Is there a tutorial or a clear example somewhere of connecting to an oracle database, executing SQL statements, storing and retrieving data? another question: In the manual there are about 16 functions listed, but I've seen people refering to functions not listed in the manual.... is there a place where I can see all the functions? Thanks Ed