Start here for spots:
nswwavesailing.org/spot-guide/There is always a crew around at Brighton Le Sands, Kurnell, Wanda, Long Reef in a NE or Southerly.
Koichi and a few other guys sail down at Bondi.
See the guys for at Windsurf and Snow up in Collaroy for windsurf, sup and kite gear.
For wether reports check Seabreeze and Bom.gov.au. Seabreeze give you a general idea but forecast strength is usually bit off. Bom.gov.au is a bit more accurate.
If you are strapped for transport Baywater Car rental on William Street in the city has "cheap" cars.