Great country music recording

There are a lot of great suggestions here and since everyone else is ignoring your pedal steel requirement, I will, too.

Asking for coutry music suggestions is like asking for classical music suggestions, you'll get everything from Satie to Wagner and that's not a lot of help in narrowing things down. Julie Miller and Billy Ray Cyrus are about as far apart as Satie and Wagner

I seem to be attracted to the music that sort of out there between genres. Lyle Lovett's an example; you're just as likely to hear a cello as twin fiddles in his arrangements.

One of Willie Nelson's most interesting is 'Teatro,' a blend of country and with the New Orleans influence of Daniel Lanois, and the above-mentioned 'Stardust' rendition of old standards (or lounge music, depending on your perspective.)

The Mavericks, Los Super Seven and Rick Trevino mix country and Latino music, which leads you to Flaco Jiminez, and you have to learn some stuff about about the European colonization of Mexico to figure out why a Tejano is playing an accordion.

You might consider Guy Clark and Townes Van Zandt as country but you'd be as likely to find them filed under folk in some record stores.

Emmylou Harris is comfortable with, and good at, all of it and there are lots of others who mix new sounds with what you'd think of as traditional country music, Lyle Lovett, Ry Cooder, Asleep at the Wheel, Dwight Yoakum (though in the case of Yoakum, it might be a stretch to call Buck Owens 'traditional' country.)

And speaking of traditional country, Iris DeMent, Nickel Creek and Gillian Welch are doing traditional but it's just another step over to Alison Krauss and Buddy and Julie Miller and a mix of styles.

You can start with The Byrds' 'Sweetheart of the Rodeo' and work your way through the Cosmic Cowboy detour, though I recommend you stop pretty quickly after you start.

An interesting sampler is 'Rhythm, Country and Blues,' though only a few of the rather strange pairings really work and they're all over the top.

So, lots to listen to.

Ray Charles' Modern Sounds in Country and Western Music

Townes Van Zandt. Steve Earle, another favorite of mine, said of him, "He's the best damn songwriter around, and I'll stand on Bob Dylan's coffee table in my boots and say it!" (That's a pretty good paraphrase from memory.)
I go along with Lucinda Williams, and would add "The Flatlanders," especially their first album, "More A Legend Than A Band." Also, anything by Gram Parsons.
An interesting new one I picked up recently is Ramsay Midwood's "Shoot Out At The OK Chinese Restaurant."
Sorry, they're not mainstream, but that's why I like 'em.

All of the above suggestions are good.
I would add:
Kevin Welch
Jim Lauderdale
Jimmy Dale Gilmore
Kelly Willis
Gillian Welch

For especially good steel guitar work:
Waylon Jennings had a steel player named Ralph Mooney, he was one of the best in country music. A couple of albums really stand out, "This Time" "Honkey Tonk Heroes" "Lonsome O'nry and Mean" are my favorites, there are more.
The Flying Burrito Brothers had a really good steel guitar player named "Sneeky" Pete Kleinow. Their albums are good, especially "Gilded Palace of Sin". While we're on the Burritos, as someone mentioned above, anything by Gram Parsons is good.
I have been a big fan of country/alt country for a long time. Most of the recordings are very well done and sound great on a good system.

Yes, I am more into Alt type country.

Lucinda Williams, Roseann Cash, Kim Richy, Steve Earle, Allison Kraus are great picks from my side of the fence.

Rodney Crowell's -Fate's Right Hand is great.
The American Recording sessions of Johnny Cash are stone cold great.

Jim Reeves, Patsy Cline, Hank Williams (from no to any number), Loretta Lynn have great songs.

Decoration Day by the Drive By Truckers is a recent one I have that is a lot of fun.

Flatlanders is a wonderful pick.

Great selections by everyone really. Have Fun!!!!