Where is the best tunes

Ask your dancers to bring in their favorite tunes, on CDs or music files.  Don't play them blind, because many aren't danceable (see the above criteria), but collect them for your future programming.

Search through Spotify, iTunes or Amazon mp3s.  If you buy tunes, you can deduct them as business expenses if you're a professional DJ or teacher.

Many complete tunes are now posted on YouTube, often with just a single image of the cover art as the visual.  Then there are several online sites that convert the YouTube videos to mp3s, and a hack using Safari, giving you the entire song for free, but the monaural sound is often too low quality for a dance.

Try the listening stations at record/CD stores, before they completely disappear (oops, too late).

Trade favorite tracks with other dance DJs.

Listen to the radio, including Pandora and internet stations.  Stations often post their playlists.  Internet and satellite stations (like Sirius XM) also give metadata of the current tune.

This website

Good Choice

I believe that coming up with songs appropriate for each dance form is up to the DJ's experience as a dancer.  "This sounds like a cha cha to me."  His/her intuitive hunches are what make every DJ different.  There are no correct answers, and each DJ will have his/her unique sense of whether their tune choice works well for that dance, or not.  Then the dancers each have their unique sense of whether their dance choice works well for that tune, or not.  Everyone is following their hunches, but a part of this process is also objective:

After we come up with an intuitive guess, then we can easily check the tempo, to see if it's within 10% of the sweet spot tempo (below).

We easily tell whether it has a driving high energy or if it's gentle/lyrical, to match to the tempo being above or below the sweet spot.

But coming up with that first intuitive guess is what makes each DJ unique.  My tips don't want to influence that individuality.  The suggestions on this page are just to help increase the percentage of tunes that make the dancers happy.

Not to do

Don't choose tunes primarily because of the lyrics, title or clever name of the band.  Most dancers don't listen to the lyrics when they dance.  Dancing is a very non-verbal activity, so choosing a tune primarily because of its lyrics has almost zero value to the dancers.  Besides, dancers come to have fun dancing, not to admire how well the DJ strings together a series of songs on a special topic. 

Don't choose a tune primarily because it's unusual or weird, at the expense of it being an effective dance.  Don't get me wrong — weird music can be great when it's danceable, but the first priority is meeting the above requirements, motivating the dancers and having tempos perfect for their energy level.  If these are met then yes, obscure is fine, and weird is fun.

So the key word here is "primarily."  If tunes have a special theme and are wonderfully compelling to dance to, then there's no problem.  But too often a DJ's quest for special themes or lyrics leads them to dig up tunes with undanceable tempos and hard-to-hear beats.

All suggestions have exceptions.  Occasionally (rarely) the words will be important, like song lyrics about a father and his daughter, played for the father-daughter dance at a wedding.  But in general, lyrics aren't the reason to choose your dance music.