Here are some audio related sites Minirig use and recommend:

• Elliot Sound Products: the master resource for DIY (and non DIY!) audio knowledge. Start here. Always. Good sanity check against the mass of audiophile silliness out there.
• Australian Technical Production Services: another great resource for Aussie DIY PA.
• DIYaudio forums: massive resource with long and involved discussion forums on design and contruction and tweaking of audio gear.
• Rockby components. Great source of low cost but quality electronic parts in Melbourne Australia, especially capacitors.
• Speakerbug: quality capacitors, inductors and resistors and other DIY speaker components.
• Gainphile’s audio blog. Open baffle, Waveguides, Class D amps, active crossovers… great Melbourne audio blog with a depth of info.
• Red Spade Audio blog: another Melbourne audio blog with a depth of information and great projects documented.
• Muff Wiggler: Excellent resource for everything Synth.