Markets:

QUEEN VICTORIA MARKET - CBD
$~$$$ (Aug 2012)

http://www.qvm.com.au/qvm/qvm_home.aspx

Address:
Corner of Victoria & Elizabeth Streets, Melbourne CBD
Tel: (03) 9320 5822 
Opening hours:
Tue & Thu 06:00-14:00
Fri 06:00-17:00 (general merchandise to 16:00)
Sat 06:00-15:00
Sun 09:00-16:00
Mon, Wed & Public holidays Closed
Features:
Australian souvenirs & products
Groceries & food market (seafood, meat, fruit, delis)
Recommend:
sheepskin products
Comments:
For those trying to hunt for some Australian-made Ugg boots (not those of the U.S. trademark 'UGG Australia' though), you can find a good selection here.  Or if you wish to buy all your Aussie souvenirs, you should be able to find all that you need here.

DANDENONG MARKET - Dandenong
$~$$$ (Aug 2012)

http://www.dandenongmarket.com.au/

Address:
Corner of Clow & Cleeland Street, Dandenong VIC 3175
Tel: (03) 9701 3850
Opening hours:
Tue & Sat 07:00-16:00 (general merchandise from 08:00)
Fri 07:00-17:00 (general merchandise 08:00-16:00)
All other days & public holidays Closed
Features:
Australian souvenirs & products
Groceries & food market (seafood, meat, fruit & delis)
Comments:
This market is located in the eastern suburbs so if you happen to stay on that side of Victoria, it may be a closer choice than going to Queen Victoria Market (although this one is not as big), however we found that some of the Australian-made ugg boots were a little cheaper than those at Queen Victoria Market (but colours & styles are more limited since fewer stalls to select from).
But I do like how the buildings & shelters for this market were recently rebuilt so it was very neat and clean to shop in.