Links! Links! Links!
(in no particular order)

Federal Communications Commission
Everything you wanted to know about your favorite Federal branch can be found on the FCC's comprehensive web site. Reams of information on daily actions and petitions, proposed rules changes and much more. The Audio Services Division has FM and AM search engines which are lightning fast. The Video Services Division has the TV search engine.
Radio Locator
Although the formats haven't been updated in ages, it's still a very useful site for determining rough-estimate coverage areas of both AM and FM radio stations.  Has direct links to station websites, streaming links and Google Maps. (formerly RECnet) is a valuable resource for unearthing all kinds of FCC data for FM and TV stations, as well as helpful for prospective LPFM applicants in finding open spaces on the radio dial. They're also big into Japanese music and offer a long-running J-pop and J-rock streaming station.
World Radio Map
World Radio Map has radio station listings for hundreds of cities all around the world, including the United States.  Includes links to streams and great pictures of transmitter sites in many cities.
Television and Radio in Southwest Alabama
Keep up with the goings-on in Mobile and coastal radio and television with this thorough site.
The Worldwide TV-FM DX Assocation
Home of a comprehensive list of FM stations across North and Central America, their database is a valuable tool for FM DXers. 

Monster FM

A small but growing engineering group for both full power and LPFM stations and prospects.  Interested in whether your town can fit a low power station in, or whether your station can do that upgrade?  Check these folks out.
I Take Pictures of Transmitter Sites
Like looking at photos of antennas, tower, studios and transmitters from all over?  This Facebook page is open to anyone who enjoys radio's technological side.
New England-centric tower photography for the über-radio nerds.
AVS Forum
AV Science Forum covers all kinds of home theater and HDTV subjects, but of particular interest are the market-by-market forums for HDTV reception and discussion.  There are forums for Birmingham, Mobile/Pensacola/Ft. Walton Beach, Montgomery, Huntsville, and Columbus.
KFFA King Biscuit Time Blues Show
The longest running radio program anywhere, the King Biscuit Time blues program is now available online from KFFA in Helena, Arkansas, broadcast live each day from the Blues Museum downtown by Sunshine Sonny Payne.
Robb Radio on KCJJ
Robb Spewak is co-host of the above-listed Mike O'Meara show podcast, but he also hosts his own radio show on Iowa City's KCJJ-AM 1640.  His knowledge of music from times past is unsurpassed and his timing and delivery are really fun to listen to.  If you like a diverse selection of oldies but goodies, talked up the way jocks used to do in the good old days, check out this show.  Available in mp3 format.
Atlanta Area Radio
Not just a dial listing for Atlanta AM and FM, but also some absolutely wonderful histories!
A wonderfully useful tool for locating nearby DTV signals and plotting reception graphs and other geeky stuff.  Essential for setting up an OTA antenna!
The AM Stereo Page
Some folks are still hanging onto good old fashioned C-QUAM AM stereo.  It's a big improvment for music on AM radio and sounds much better than most people give AM credit for.  A few stations still run it, and they're listed here.  Meduci, who hosts this list, also sells a fine AM stereo tuner and decoder board to diehard AM stereo fans.
William Hepburn's Worldwide Troposheric Ducting Forecasts
VHF Propagation
Sporadic-E and Estimated MUF
If you're into FM DXing, these are indespensible tools for predicting tropo sessions through the southeast and world.  Use this to find the optimum time to hunt out elusive distant radio stations.
A great tool for shortwave listeners, it helps you discover what you're listening to just by putting in a frequency.
FM Fool
TV Fool
Don't be fool-ed by the name, these are useful tools for the radio geek.  Find and plot transmitter distances and more.
Radio Station World
A global directory of streamable broadcast stations.
RDS List
Although it hasn't been updated in over a year, this is still an interesting and useful tool for discovering what stations are broadcasting over their RDS feed.
A handy text list of known and suspected LPFM formats, with links to station websites and more.
Columbus DTV
Information on DTV in the Columbus, Georgia television market.
Lagniappe: Media Frenzy
Mobile free newspaper's media column is available online and a good source for keeping up with coastal radio, TV and papers.  
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