When you build an audience, you don’t have to buy people’s attention - they give it to you. This is a huge advantage. So build an audience. Speak, write, blog, tweet, make videos, whatever. Share information that’s valuable and you’ll slowly but surely build a loyal audience. Then, when you need to get the word out, the right people will already be listening … via Jason Fried (to add to that: Hopefully at the point at which you have that audience, they spread the word on your behalf).