This free application for Chrome gives you the ability to search for Spotify songs and play them in the browser. You can add the song to a playlist or save it to your library.

You don't need an account with Spotify, only to search for the songs you like.

You can search using a variety of parameters, including artist, album, genre, and many others. You can also get an idea of the style of the song with which you want to listen. The application allows you to simultaneously play a song in the background as well as the ability to create a playlist.