Sta.sh
First off, Kayla B, from A Bromance in Bohemia on soundcloud.com. She has created numerous fantastic Sherlock songs, all with ranging character points of view. It is absolutely impossible to choose my favorites so I'm just giving you the link straight to her profile: [link]
She also has some brilliant Pilot Rock, songs about the radio series cabin pressure, staring the equally brilliant Benedict Cumberbatch.
Whooliganful, also on soundcloud, has a absolutely fantastic voice that I instantly fell in love with. Her song are heartfelt and sometimes fairly sad, but thats what you get with reichenbach agnst i guess. Absolutely beautiful music, my favorite is Reichenbach (fade). Check her out here:[link]
Another amazing artist on soundcloud is badwolfonbakerstreet. She has created an amazing song about the aforementioned Mr.Cumberbatch, one that the more head-over-heels fangirls will enjoy ;D
I am sure there are many many more fantastic Shrockers out there which i have yet to find, so if anyone has any recommendations leave them in the comments so we can all enjoy
Laterz,
mrs.watson xoxo
Obsessed 
Seems all fandoms have nice musicians! (Gonna fave this journal so I don't forget xD)