You could try
Nerd Sniping, which is how I got involved.
A mom at our church was talking to my wife about how their robotics team had problems at state because of programming, so my wife volunteers me to help out.
Once I actually met with the team later that year, they had a problem they were having in preparation for an off-season event (completely unrelated to programming, but we all know it doesn't really matter what the problem is), I was hooked on FIRST in about 10 minutes, simply by helping them solve the problem.
The moral of the story: FIRST

impressions are important, and if someone feels that they are contributing something of value, they are going to also feel like a member of the team.
Also, ditto on the spouse involvement. My wife is an engineering grad student, we're both hooked on this program, but it would be very very difficult to commit the time we do if we weren't sharing the experience.