In House Radio with Jeremy Petersen is a weekday, hour-long radio show out of Pocatello, ID I should have recommended long ago.
So: Jeremy's on top of most of the new releases I mention here, as well as lots of the big ones in the indie/rock/folk world I don't. You'll hear pre-release tracks; the other day, he spun a new Lucinda Williams song from the upcoming West.
Every day has a featured artist or two; recently, the honor went to the deserving Ron Sexsmith, and the In House listener was treated to several songs from the new Time Being along with a few well-chosen older tracks. And most sets are peppered with plenty of oh-wow classics (hearing handpicked singer-songwriter gems like Damien Jurado's "Simple Hello" and Freedy Johnston's "Pretend It's Summer" amid all the best new stuff is almost too good to be true). Peterson fills in the gaps with just enough interesting commentary to make it feel like radio.
In short, it's a great way to keep up in daily, commute-friendly hour-long doses, and fortunately it's available in podcast form. I recommend the Sexsmith show to start (beyond Ron, the playlist crams in Karen Dalton, Catherine Howe, Andrew Bird, Kristen Hersh, Richard Swift, George Harrison...singer-songwriter heaven).