Get this in your earholes, via
Firstly, and probably most importantly, my mic is an Audio Technica 4040. Not the greatest mic in the world, but it's an affordable wide condenser with a 75 hz rolloff and a nice, flat response. So it gets rid of the low band energy and doesn't make any bumps in mid or top range, which makes it easy to sweeten without too much corrective EQ. Good times.
Next, that runs into one of a pair of API VP 26 preamps (which you can have custom built for you by the incomparable Michael Zucker). These are class-A preamps, so they're super clean, lots of headroom, and sound great without adding too much color. In fact, I have a red and a blue one for different, albeit subtle, levels of aggressiveness. Great for guitars too.
Next, we have the Apogee AD8000 that I picked up for a song at the Nice Package Recording Studio (a song being several monies) during their renovation. This AD/DA (Analog/Digital and vice versa) converter is a powerhouse. It sounds fantastic and I've never had a single issue with it.
Finally, we run into my Lynx AES16 sound card, which gives me sixteen channels of audio. The Lynx was recommended to me, so I got it. That's the end of that.
On the PC side, I custom built a tower that runs Cubase 7 artist, mostly because Pro Tools is too damned expensive and it limits what kind of hardware you can use with it. I didn't have money for an Aurora converter, and I'd been using Cubase more and more over the years, so here we are.
You may notice that this sounds like overkill for voiceover. It is. I also record my band, so it was important to me to have versatility and options for expansion down the road. If I had the space, I could probably record an entire band with this setup. You don't need all this. A simple (but decent) mobile preamp with a USB out, a solid mic, and a laptop are all you really need. But where's the fun in that?
Oh, be sure to use decent cables too. A Mogami sounds a hell of a lot better than some kinky, no name cable from Radio Shack. Definitely worth the investment. Mike Z can build those for you too. He's a handy fellow.
For audio sweetening, I use a handful of plugins for EQ, compression, mastering, delay, reverb, and any other effects I may need. More on those later.