Why not offer it as free to incubators or other startup communities that have startups.
Offer free support and do webinars once or twice a week to demo the software.
Email the creators of a bunch of startup related podcasts, make offer to Jason Calicanis to disseminate, tweet it, etc.
Have a blog on your site, etc.
Give it away for free for now.
I feel I must add some comments - since "giving it away for free" does nothing to help the customers - you have to help them succeed with it. So run promotions, find out about your customers and engage them in Q&A and support and help.
Given the nature of your product you are in a great position to bring that help to them
Another idea is to run a contest for "best video" of some sort - either a best "how to" or anything creative - to get people to use your softwaer and share it with you and the community. The rules are only that they make it with your software.
You can have a free year - totally free year for intros - and anyone who enters the contest gets more freebies - winner gets something, etc.
Just some thoughts on what I might try...