The Arnold Sisters (Lindsay, Jensen, Brynley, and Rylee) have youtube channel and they every once in a while will post a dance challenge that they choreograph together. If any of those names sound familier Lindsay Arnold is a Pro on Dancing with the Stars, Jensen and Brynley have been on So You Think You Can Dance, and Rylee was on Dancing with the Stars Juniors. Their tutorials are a little fast and youtube-esque, but if you slow it down and commit to something new it's really fun! Click on the image to try a little ballroom and hiphop. 

Dance with Me USA is also a youtube channel with ballroom tutorials. Most of the videos are led by Dancing with the Stars Pros: Jenna Johnson, Val and Maks Chmerkovsky, and Peta Mutr... The sessions range from basics to cha cha, salsa, samba, and rhumba and all are easy to do in a relatively small space with little to no experience. Click on the image to visit their youtube page! (As a side note most of their videos are older, but new ones could be in the making).