Starting up a JC is hard work, but it pays off in the end. The Chicago JC started in January and so far it's been great.
I would suggest using Evite as a way to invite people to the First Informational meeting (they can see other people responding - the more that respond the more people will come). I would also suggest getting in touch with your local alum chapter, they're usually great with encouragement and providing support. Our JC is involved with an area Panhellenic and since we have to pay dues to NPC (and the JC has no budget), the alum have covered that expense for us. Just keep in mind that usually about 25-30% of your members will show up at events, but if it's not the same people every time, you've got strong interest in the JC.
I know you'll do great, and people will constantly mention to you why there wasn't A JC before this because it's such a great idea getting involved again....
LIEP,
Amy