"Your Story" has a side-box in the pages about elements that discusses electricity. It suggests you treat it either as a separate element, or as a sort of sub-category of Air or Earth, depending on your character's personality and philosophy of magic.
Electricity does have a little bit of the same problem as Fire as an element - you have to get creative to do more with it than hurt things. Evocation is pretty limited in the sense that it's not good at doing small, detailed manipulation, so don't plan on using it to hack a computer.
Some spells I'd expect to see:
-A blast of lightning to blow stuff up
-An electric cage, holding someone in place
-Stunning or tripping someone by using a targeted electrocution to cause muscle spams
As for focus items, I could imagine using a bracelet or ring of copper wire, a magnet or lodestone, or anything with a symbolic lightning-bolt or thunder-cloud motif on it.
Mr. Death did make a good point that hexing can't be controlled enough to let you decide HOW something gets broken, just that it WILL be broken. Also, I doubt that even Thaumaturgy can magically interact with technology on a detailed level. Still, with a high enough score in Craftsmanship and maybe an Electrician stunt, I would let you attempt to repair hexed items - as long as you can control yourself well enough to not hex them even more in the process (discipline rolls or invokes/compels would be appropriate).
Finally, I'm really not sure what you're looking for with "tailor made transformers and capacitors". Anyone with the Craftsmanship skill can roll maneuvers/declarations to build useful stuff. I wouldn't let you build that kind of tech with magic, though.