Bird Identification: Need help with a family of birds living in my back yard!, 1 by VegasBurds

VegasBurds wrote:
I spotted a mating pair of these in the back yard, along with a very well hidden nest. I live in the Las Vegas area and I've visited a ton of sites trying to pin these guys down. I'd love to provide some nesting materials or food to the babies, so it's for a good cause. I'd prefer to help out knowing a little more about the species in question first. That and I'm just really curious...

Thanks to anyone who can offer some advice.