One of my favorite, top tier, A List voice actors is Scott Rummell; a terrific promo and trailer voice. He's a big league talent you've no doubt heard over the years. A Disney voice, Lee Jeans and much more. He also seems like a very generous and nice guy. (his picture is down below)
Here's a link to Scott in an L.A. studio recording a new commercial demo. Watch the process. Much to learn from this. It runs about 20 minutes. You'll notice the session was "light and breezy." The guy producing the demos is Chuck Duran of "Demos That Rock Studio" in L.A.
And here's a link to a really entertaining TED Talk Scott gave where he speaks about how he got started in voice acting. Very enjoyable. I highly recommend you watch it. It's truly inspirational and also runs about 20 minutes. If you've been sitting on the fence about getting into voice acting, maybe this will give you the kick in the pants you need. Even if you're not a voice actor, check it out. The power of persistence comes through loud and clear.