Congrats on recognizing that you don't have the expertise to do what you'd like to do. So many people figure that out after it's too late.
The best thing to do is to make a complete list of all the functionality you want your website to have/be/do. This list must be comprehensive. Then, break that main list down into three smaller lists:
1. Your must-have list: this is a list of the functional elements that your site cannot go without.
2. Your nice-to-have list: this is a list of the functionality that is not critical, but would really add to the user experience.
3. Your in-my-dreams list: this is a list of all the things that you feel are too time, finance or labor-intensive to do, but would be super cool.
Then, on a sheet of paper, do a mock-up drawing (or if you're good at graphics, put this in a design program) of how you want the site to be layed out. What you're looking for here is placement of various elements, not design. In professional terms, what you're doing is creating a first draft of your wireframes (you'll have to get these professionally redone later, but doing it this way for now is okay).
Only afer you've done these steps should you try to find someone to help you build the site. It will also be helpful to determine whether you're going to pay someone or if you want to share equity or profits.
Then the next logical place is to start asking all the technical people you know for referrals. It's best to work from referrals. Be sure to interview at least three possible consultants so that you make sure you find the best person to help you.
Lena West is the CEO and Chief Strategist of xynoMedia Technology, a New York-based firm that helps high-growth companies leverage the power of social media, blogs, podcasts and online communities.