G'Day Ardy,
Check this video out...
http://www.etrailer.com/tv-FAQ-Changing-Brakes.aspx This site has some great maintenance videos and also a great source of spare parts for your FW trailer. There is also a trailer brake place in Queensland who have a lot of parts for US sourced trailers such as disc rotors etc. at reasonable prices.
Basically to adjust the brakes, you tighten them up until you can't turn the hub by hand, then you back the adjuster off until the brakes rub lightly. You can buy a fancy brake adjuster tool or just use a screwdriver. Not a difficult job either way.
Cheers
Alec