How do you create this audio effect in the guy's voice?
I also like the girl's voice when she does the count down. What tools do you use to create these effects? Can I use Audacity?

Thanks

I think is the flanger effect

Definately a flanger with some heavy compression, and perhaps a chorus for its stereoness. as far as the girl, its an EQ with all the bass and low mids removed as well as the top end removed (simulating the frequency limitation of old phones and equipment)

Would I first start out with a flanger and then add the compression? What order do I apply the effects?

I would use a compressor first, then the flanger. That will give you the most noticeable flange sound. If it sounds too much, you can try reversing the order. One thing about flange effects... For this kind of sound you'll want a slow rate, and a large amount of depth. Set a fairly deep depth first, then play with the rate setting until you get what you're looking for. A high rate setting will sound really weird, like their underwater or something.