I'd say anywhere from a 12m to a 14m would be fine, in winds from 14 to around 25 knots (providing it's a bow), even though a 12 may struggle in the 13 knot zone.
As you're a beginner, it would be easiest to start on a bow kite, also safest too due to the depower, infact there is really no reason to use a C kite until you become fairly advanced.
I have a sligshot turbo 2, but there are plenty other great kites out there that others swear by eg waroos, monkey griffins etc. It also depends upon your budget.
Try get the later model kites - the main reason being they have better safety system.
For the board, I rekn a big board is always easier so between 130 and 150 is usually good (I have a 147). If you're up on the northern beaches, which is also where I kite, then you'll want one with a bit of flex to soak up the chop, but not too much, you'll find that out when you start doing pops.
Go into one of the stores over there - such as balmoral boards or... I forgot the other one's name, but its near fisherman's beach... they'll show you a few kites too and talk you through it.. they know a lot more than me
