SQL & PL/SQL

Right now I am writing a SQL script to create a schema and build the objects of this schema....

I use a .net winform program to run sqlplus to parse this sql script ...

The problem is that the schema name and the tablespace's location and the sys password must be input by the user, so my SQL script should use these runtime input parameters instead of const parameters....

So, how to use parameter in SQL script ...........

Are there some example scripts in oracle home directory for me to refer to????