If you would like to create a physical database from a logical database you can use the designer tool of Oracle.
I am not sure where you could get the documentation for it,
but designer is a very powerful tool which not only is used to create but reverse engineer and in some cases edit to
i afaird that No book will tell u the right size of the SGA rather book will tell u how to think before sizing i.e, it really depands on the workload of the database, how much entries u may have each day and on monthly bases. but one thing u should kept in ur mind to logically devide ur database based on the departments . that is try to think about different tablespace for diff.departments and make multiple files in each tablespace.SGA ROUGHLY SHOULD BE 50% OF UR RAM
and RAM should be according to workload.