Sorry if this is a little spammy/self promotional - I've created a project that I think would've helped me out when I started working in interactive sound 7-8 years... and this is where I'd be looking for information. My name is Mark McKeague, I'm interaction designer / sound artist now founded a company called Dentaku.
We've created a product called Ototo, which is a 'musical invention kit'. This allows you to connect sensors and touch inputs to interact with sound, either on the inbuilt synth or over USB MIDI. Our idea is to make it easier to get started with electronics and sound, but also to allow flexibility for people to do more complicated projects.
Have a look at our Kickstarter page, and if you like the project we'd really appreciate the support.