Use the register parameter for the pg_ctl program.
The data directory should not be stored in Program Files, the location of %ProgramData% is e.g. a good choice.
pg_ctl.exe register -N PostgreSQL -U some_windows_username -P windows_password -D "%ProgramData%/db_data" ...
In newer versions of Postgres, a separate Windows account is no longer necessary, so the following is also sufficient
pg_ctl.exe register -N PostgreSQL -D "%ProgramData%/db_data" ...
Details are in the manual: http://www.postgresql.org/docs/current/static/app-pg-ctl.html
You need to make sure the directory D:/Program Files/PostgreSQL/9.0.4/db_data has the correct privileges for the windows user you specify with the -U flag.
Btw: it is a bad idea to store program data in Program Files. You should move the data directory somewhere outside of Program Files because Program Files is usually highly restricted for regular users - with a very good reason.