You need to find an authorised person who can conduct the ceremony at the venue you have chosen, at the date and time you want and find out what is legally required in the country you are getting married.  In Australia, see 'What to do next' in the Celebrant Services section on this web site or visit www.ag.gov.au/celebrants  To find a celebrant in your area visit  www.civilcelebrants.com.au  or http://www.ag.gov.au/mclisting.