Which one should i get for my build?

I would go for the ASUS P8Z77-V PRO. Good price, and very standard ASUS motherboard.

The ASUS SABERTOOTH Z77 is over-priced. The large heatsink/cover looks nice and will match your case. However for $70 more, it is not worth it.
 

No, you will not need to buy one. It appears to come with a wifi module and 2 white antennas that are connected by wires to the module.