I'll add but it has already been said by other's:
Facebook event page is the way to go. You can invite people via e-mail from there even if they aren't on Facebook. And in the weeks/days leading up, you can post pics of things that you are working on, invite them to bring favorite music, instruct on where to park etc.
If you really want to grow this, it takes time. We had our first party in '92, and maybe missed only 4-5 years since then. Last Friday night we had 57 I think. 1) set your expectations when you start out very low. Even if it just you and y our SO an one or two other "fun couples" figure out how to just make it fun. And 2) you have to "cultivate" your guest list over the years. Mix social circles, family, work, hobby's, church, whatever. Find the fun people who can have fun at a party even if they don't know hardly anyone there. Drop people off the invite list if they don't respond, or even if they come but don't seem to enjoy themselves. Over the years it will snowball. We have such a great group, they start asking me "are you having a party this year????" in Feb and March. If they come and have a blast, and like/love Halloween, they WILL come back the next year.
Good luck, don't lose faith...