The case fans use molex connectors. I set mine on LOW and plugged them into the PSU.
The front panel connectors? RTFM.
But the year is still young so...
The front panel connector is described and located on the drawing in Section 1-7 Internal Connectors. It's labeled F_PANEL.
Other comments about the Antec 900 case: I like them. I have three. Great cooling. Cable management could be better. I modded my cases with extra holes cut into the motherboard tray:
Antec 900 case mods for cable management:
http://www.tomshardware.com/forum/264112-28-antec
It just aggravates me a little that I have to do something like this.
Neither the Antec case nor the Gigabyte motherboard include a system speaker.
Where to buy a small motherboard speaker
http://www.cwc-group.com/casp.html
If you find a small speaker from an old case, just magnetically stick it to the PSU in some out of the way place.
While I am thinking about it, look over the checklist at the beginning of this thread:
http://www.tomshardware.com/forum/261145-31-read-posting-boot-problems
It may keep you from making any of the really common noobish mistakes.
Good luck. Let us know how it goes.