My grandfather signed up for it, so I'm getting the spam. Apparently he changed his password, but they are still sending spam emails from him "via Tubely". From googling this, it seems that if you signed up for Tubely you can click the "help" tab, then "FAQ's", then "How do I delete my Tubely Account", then following the instructions in the please-confirm email they send.
Important note: SIGN UP FOR NOTHING WITHOUT FIRST GOING TO GOOGLE.COM (OR ANY SEARCH ENGINE) AND TYPING IN THE NAME OF THE WEBSITE AND THE WORD "SCAM". That should turn up results that you need to see before signing up for ANYTHING online! (sorry for the loud volume, but that needs broadcast widely)