Currently, there's not really a lot of places I want to link to... In fact, I'm just starting with two links. Have fun.
Detective Conan's Mystery Files
This is pretty much the best site I've found for Detective Conan scan-trans, and it also manages to be among the best otherwise, among Detective Conan sites in English. If you're just starting in on Detective Conan, this is where to start.
Kid - The Phantom Thief
There's only a few Magic Kaito sites in English on the internet. This is the only site of the ones I've been able to check with more than a single story availible in scan-trans. It also seemes to currently be the only friendly one in English that's currently up and running (as opposed to merely up). Oh well...