Do you guys know any good books or tutorials on the topic of isometric games using SDL or SFML?

Are you talking about 2D isometric, or 3D with isometric projection?
Also, doesn't really matter what middleware (SDL/SFML?whatevs) you use in either case.
Assuming you are talking about pseudo-3D-that-really-is-2D-isometric-tilebased, take a look here:
http://gamedevelopment.tutsplus.com/tutorials/creating-isometric-worlds-a-primer-for-game-developers--gamedev-6511
or here:
http://www.codeproject.com/Articles/28608/TetroGL-An-OpenGL-Game-Tutorial-in-Cplusplus-for

but, really, just google for it without restricting to SDL/SFML and you'll find lots of info.