Welcome. Great post. Sounds like your story is very similar to our own, so we might have some useful advice.
We got started doing street action with just two people, the founders of the group. We started the group because NY911Truth, where we got started with 9/11 truth activism was run by someone we didn't at all trust and there was too much disagreement in the group about basic principles and strategies to get anything done.
And for some time I feel that we were more productive doing outreach with two people than the twenty or so regular members of that group. We went out more often. We went to diverse locations around NYC while they stayed in one place. We had a very accurate and responsible flyer while theirs was ridiculous. We had very positive interactions with people who very rarely left with the impression that we were nutty. Can't say the same about the other group. Two people really can accomplish a lot.
Not too long after we got started a couple other people joined the group and that made our outreach even more productive as we needed two people just to hold our banner sign. With three people we could talk more easily with others and someone was free to take pictures.
http://www.flickr.com/photos/truthmove/sets/
But more importantly, as you suggested, a small, tightly knit group of those who joined because they have a similar approach can operate largely by consensus rather than democratically. That becomes less possible as the group gets bigger. You might think that it would be best for a group to grow as large as possible. But that seems to open the group up to infiltration and democratic subversion. Yes, democracy is generally good. But these groups really need to have enough structure to begin with that people either join because they agree with your structure of don't because they have a different vision.
Our group never had more than five core members. I've noticed that most 9/11 truth groups have no more than about ten core members. Beyond that you risk a split, something we have seen in places where interest was high. It all depends on your goal. If you want to do street action, a small group is less imposing and totally effective for education and outreach. If you have a venue and want to do regular meetings, you might be trying to draw a large audience of the curious and uncommitted.
Now the original members are scattered around, no longer able to do street action together. I am living in Los Angeles and thinking myself about how to start a new group out here. The groups already in LA are really lame, so as with NYC, it seems that starting a new group could really be good for the movement. But where do I start?
There seem to be very few people who haven't already made up their mind about the movement. Those concerned have taken action. Those who are not aren't likely to get into it now. I could try to draw those from the other groups to join mine, but that generally creates tension. My best recommendation for recruitment are to get out on the street with flyers that encourage participation. To hold an event that draws people based on their other related interests and encourage their participation. And as you suggest there are many places online where you can promote your group.
That brings me back to my main recommendation.
In order for you to get people interested and participating you need to spend the time to organize your project in a way that suggests to people that it's not casual and makes it clear to them that you have a specific strategy in place. We launched TruthMove with our website that had a lot of content and represented our strategic orientation. If people were considering getting involved they could see exactly what we intended. That prevented us from having to describe it to each new person. Consider our forum. What's on topic here is defined by the content of the site.
Also, one way to encourage participation is to orient yourself around the bigger picture, something I think people should do anyway. People may not be all that interested in fighting for 9/11 truth. But they may be really invested in all of the values that are central to the movement. Transparency. Historical accuracy. Independent journalism. Constitutional solvency. Make sure people know that you care more about these principles than the specifics of 9/11. It's not about planes or buildings or warnings, it's about fighting for truth and justice.
Now, about infiltration or disruption. The best way to prevent that is to make it very clear in way suggested above, that your group is about certain things and not about others. That your group uses certain strategies and not others. That your group is founded on certain kinds of communication and not others. Like the forum, if you don't set the expectations from the get go, people can come in and start negotiation with the rules, and that allows clever people to create chaos. When someone comes along don't be afraid to make the rules very clear to them.
Also very important is trusting your intuition. This is something that doesn't get talked about much in this movement but I rely upon greatly. If someone seems shady, you HAVE to be willing to tell them that their behavior or strategy doesn't work in your group. The stakes and your time are too valuable for you to be limp on this issue. If someone does something or says something that doesn't fit with the character of the group, you HAVE to make that clear. You have to be willing to kick people out, and make it clear when people join that you are willing to do so. You should be able to clarify to people why that's important. Those serious about taking action should respect your concern and actually find it welcome.
And a subtle point. If someone seems like a sociopath or like they are wacko, don't feel like you have to let them come back just because you are jazzed about someone having shown interest. In my personal experience those who have been investigating me under the premise of interest in the group have seemed clenched up and unnatural. Those in the movement who I assume to be infiltrators are oddly distant and give off subtle cues indicating that they aren't being totally genuine or open. You need to trust people who you are going to work with.
Hope that helps. Let us know if you have any more questions.