if you use the tone cloud part of the app (you do need an internet connection for this feature) then most of the people who have uploaded tones tend to do so by either artist name or by song, so for example of you wanted a sound similar to Jimi Hendrix on the song Little wing you can search by just Little Wing, Jimi Little Wing or Little Wing Hendrix and it should bring up all tones that are already uploaded under those key words. 

I just did a test search for Chris Stapleton and approximately 40 tones came up so i'm sure there would be one similar to what you like, i tried a few and they sounded pretty nice as well.

When you do a search you get the option to download the tone to your spark if you like it or you can just hit the play icon and use it without having to download it so you can try a few out before deciding which one you like, obviously if you do download it you will have to save it as one of the presets on the Spark  but once it's there you are also able to tweak it to your own tastes.

One thing i will say is if you are searching for a tone it's worth trying a few out because even though you may want a Fender Princeton sound for example you may find the tone cloud version that sounds closest to the album version you are looking for may use a Dumble or Matchless type amp but these are basically hot rodded Fender amp at heart anyway but this is really where the try before download feature really comes in use.

if you need any help feel free to ask and i'll try my best to help you out any way i can.