we had our engagement in August - and it snowed during the day so was damn cold that night! i work skirt and nice dressy top - was going to look for a dress, but decided that the top was what i wanted, and if it was TOO cold i could swap for dress pants for warmth (which i did later in the night!). i just wore tights and boots with long skirt to at least keep me a little warm. i always like to think in "what if's" and have a change of clothes if need be. i got skirt from a little boutique in town ages ago - was just a straight black skirt. top i got from undercoverwear (haven't seen a catalogue yet where they dont' have at least one pretty floaty top)

for DD, maybe look at plumpkin patch or even chain reaction. we got the dresses for our flowergirls at chain reaction for $25 and they're gorgeous. given you're in melbourne area, maybe even look at FG - there is a little shop called purple pumpkin (i think) kinda near best and less (another option) that has some really pretty little girls dresses at really reasonable prices!

for food - depends on what you want - if you're looking at a 2pm "party" you won't need to go a full meal - more just a bunch of finger food. we cooked up a heap of home made sausage rolls and pizza pinwheels, mum bought party pies/pastries and we used the pie ovens at the local footy club. had some basic sandwich platters, then sweet food as well - ours was an after-dinner supper type thing, but you'd probably be looking at similar food for an afternoon tea. i guess you just have to keep in mind how many people might expect a light dinner to be served if it goes more than a couple of hours

no matter what you do, if you're planning on something outside - have a backup plan!

for tables, lanterns are nice, or floating candles (and if you're smart, you'll get nicely scented citronella candles!) - i don't think you'd need fairy lights unless you're wanting to give the impression that the party is to kick on into the night (and hence add dinner and supper expenses) - if you're looking at having a picnic feel, keep it very day time kwim?

HTH

BG