I'm running a niche local business online search directory, and am having trouble reaching a critical mass of businesses - enough participation that the site has value to both local consumers and businesses. It's tough to get local small business owners to take the time to sign up on my website. I'm willing to spend up to $10 per quality registration (where the business inputs accurate information), but I don't know how to best allocate this money. When I tell businesses that registration is free, they object or say "I'll take a look" but never follow through with a sign-up.
How does one best go about getting local businesses to sign up for one's site, given a budget of $10 / business?