Notice how much shorter it is? As you can see I changed the title of the form from "Your Details" to a sentence that includes the call to action. Only the required fields are in the second version. Why would you need their address when you will be calling them to follow up on enquiries? Rather than including every state in Australia, I have included the only two states that we are targeting.
Of course your form could be shortened even further to ask only for contact name and telephone number, which would no doubt have a positive affect on conversions.
Ask Yourself
Does your contact form have unecessary fields?
Can you shorten your form?
If your users have to select their country or state or province, do you include the most important states at the top of the list? (If you are tagetting USA and UK, don't make users scroll to the bottom of a drop down list to select their country! Put them at the top of the list.)