I have a 16-month-old, and if (God forbid) he turns out to be a geek, I'll have to deal with the same issue.
I grew up in a small town, and my father's shed had all the tools and space I needed. I remember ordering a 50 lb bag of potassium nitrate over the phone from a farm supply outfit, and when they asked "What do you need this for?", I joked with them "You don't want to know." I was grinding model rocket fuel in my bedroom.
The big difference today is the Internet. Nobody was around to teach me the fundamentals back then, and nobody shared my interests. I'd like to think that with an Internet connection, I would have spent less time fumbling around alone in the dark. My son may not get all the space or tools or explosives, but he'll definitely get answers to his questions.
"Never give in. Never give in. Never. Never. Never." -- Winston Churchill