Welcome aboard Peter & Family.....Its a funny ole game this camping,,,,I've been involved in camping from a very early stage both in NZ...and here in Aussie (5 yrs over your way in W.A....we had a 3b/r tent in those days)...(and I miss staying in Mandurah,,,,as it was back 20 yrs ago)
One thing you will quickly learn....is that you never stop learning...every camp...meeting new people...just seeing what the other 1/2 own & what they do with it adds up to heaps of new experiences instore for you.
1st advice I would suggest is buy the best that comes with-in your budget..BUT don't be to proud to buy 2nd hand if its in great condition....(you never know...what ever you bought may not suit you after you have actually used it)...
ASK HEAPS OF QUESTIONS.........its a great time for Family bonding when you have younger ones...ENJOY !!!
p.s.....Don't believe anything Titch tells you...hes 'Vic'......lol
Life is not about how hard you can hit, but how hard you can get hit and keep moving forward.