std_logic_1164
This is the library that defines the basic std_logic data types and a few functions.  This should probably be included in every entity you create.
The source code, std_logic_1164.vhd, contains no information about copyright or permissions to post it.  As such, I am not including it here.  If you know the IEEE's code distribution rules, let me know.
You should be able to find the course somewhere in your VHDL implementation--it has to be there one way or the other.  In particular, Synopsys users can find it in the directory ${SYNOPSYS}/packages/IEEE/src/.
std_ulogic type
  std_logic type
  std_ulogic_vector type
  std_logic_vector type
  to_bit function
  to_stdulogic function
  to_bitvector function
  to_stdlogicvector function
  rising_edge function
  falling_edge function
  is_x function