New user - creating function question

     Hello all.
    I'm trying to create a stored procedure that will accept a value and
return a result set.  I use the parameter in the select statement.  But I
can't seem to get it to work.  When I call the function, I get:
ERROR:  parser: parse error at or near "select_2"
    Could someone point me to a simple function that performs a select and
returns the result set?
    Thanks!