Hey Bullant, I think I had a vague discussion with you over on OCAU? Can't be sure, my memory is shot.
As for finding a Dewar, I really can't help much there. I just struck luck with mine and grabbed a used one from a now inactive bencher in Perth. Only thing I can suggest there is to make a WTB or such thread on OCAU and see if anybody has anything going. Don't forget to ask about the condition and vacuum of the dewar, if the vacuum is screwed then it will only hold LN2 for a day or so. A good once like mine will hold it for weeks.
As for a flask, you just need a standard run of the mill coffee flask from BigW or something like that. I have a few $10 ones and they do the job well for holding and pouring LN2 into the pot.
You'll find everybody has their own sort of materials and methods for insulation, and as you go on you'll find your preference too. Personally, I just like to keep it quick and cheap. Vaseline, paper towels and a piece of foam for full pot benching. I just grab a paint brush and go over the board with a thin layer of vaseline, then insulate the socket area with paper towels and foam. You can find good sheets of closed cell foam at Clark Rubber, should only cost you $15 or so for a nice big sheet that will last you ages.
Some LN2 suppliers to try are Freezeright, BOC and Air Liquide. Freezeright is my current supplier and they're nice people with decent prices. I pay about $3.50 a litre with delivery which is quite expensive, but just slightly better than BOC's $5 a litre charge. Try and negotiate prices when you're talking to a supplier, they can often do a better deal then their set retail prices.
The F1 Extreme Dark is a great pot, I love mine. Heaps of mass and works beautifully. Another often overlooked tool in LN2 benching is a heatgun or gas torch. I recommend the torch as it can heat up the pot faster and without blowing ice all over your board. There are different tiers of gas torches however, bunnings have a few but the only one worth having is the ~$130 version. I can't remember the model number off the top of my head, but it's far better than the cheaper stuff they have there, the cheap ones just keep going out when you put the flame in the pot.
Hopefully that's of some help, I'm sub'd to this thread now so if you have any further questions then ask away and I'll keep checking back in.