Very interesting question. Well, establishing a business line of credit these days can be a challenge, however, if you can, that is a good means of establishing operating capital. Collateral always helps, however, if that is not an option, creating a thorough business plan and model is the next, most important step in developing a reputable and attractive investment opportunity for potential investors. Once, a business plan is thoroughly researched & developed, get well versed in social media, and shopping your ideas around to various online groups. The idea, herein, being to knock on as many doors as possible and expand your networks. Keep in mind, your proprietary interests are worth protecting, so be ready to obtain a confidentiality plan to protect the company interests. Be prepared for the long haul, but be diligent. Yahoo News has plenty of stories about how people trade/barter from a paper clip to a porsche or house or what not. Be prepared to be unconventional. Hope this helps.

Have you considered using something like http://www.kickstarter.com/ or http://www.indiegogo.com/ to raise capital from individuals?

You might want to check out more specialized communities for startup entrepreneurs like http://startups.com/ or http://answers.onstartups.com/ or http://younoodle.com/
They may have more (or superior) insights.

I found these websites which are designed to connect investors with entrepreneurs, but i don't know if they will do what you want or not: http://www.raisecapital.com or http://go4funding.com/ ?

In the same way, i found these companies which directly invest in startups, but don't know if they will allow you to maintain a majority share or not: http://www.ycombinator.com/ or http://www.garage.com/ or http://unltd.org.uk/

If your company is worth over $200,000.00 sell half!