I have been using Spotify to find new music for some time and from what I have experienced, I have not found that it just plays songs that are alike.

I use the weekly playlists Discover Weekly and Release Radar (both with about 30 songs on them) and have found the to be quite eclectic.  Oddly, during the last couple of weeks or so, for some reason, the Weekly playlist seemed to be selecting musical styles that I don't like but you can hit the minus icon to curate your listening preferences even more.

Also, there are also sorts of playlists of all other types of music, too - from Americana to lists created by independent organizations (I can't recall the exact name of it, but there is one organization that selects the best independent songs of the year that is really good).

Last night I was watching old episodes of Dan Rather's AXS-TV interviews and one of them was Huey Lewis and he actually was very interesting to listen to and made great points about music platforms of today and back in the 80s and how in ways it was much easier to find new music back then because of the prevalence of the use of radio and how that impacted music popularity. 

I also subscribed to Under the Radar magazine (which is sad because over the last few years, their number of issues has greatly reduced, but it comes with a link to digital downloads with each issue).  Also, Relix still comes with a CD and a link to a digital download compilation (which oftentimes contains more songs that I like over the CD).

The magazine Oxford American also has an annual music issue that used to be really, really good, but sadly the quality of that magazine has drastically changed due to what I feel is a move away from good Southern writing to appeasement Southern writing and coverage of a much narrower spectrum of the South.

American Songwriter used to have a playlist in the magazine but they have ceased doing that. 

I really miss CMJ New Music Monthly and Paste when they would have compilation CDs.  Not only that, CMJ would put a record icon in the magazine next to articles of the artists included on the CD.