Hey everyone! I would really like to know if anyone knew an agency through which I could send a parcel (weighing more than 100 kg) to my friend in Australia. Please reply as soon as possible. Thank you!

I doubt it. At that weight you'd probably need a freight forwarder of some kind. Post Office, DHL, etc, won't touch it I don't think.

If the contents is not one solid object, you might consider re-packing it into several parcels, each within the limits of the post office.