Someone recently searched for some information on this topic here. Perhaps you've already defined your target audience and wonder now where to find them. Of course this may vary depending on your audience. First, let me say that if you've created your marketing materials to appeal to your target audience - your website, social media, etc. - then your target audience may just come to you!
Find out where your target audience goes - both in person and online. Then go there. Your target audience may attend local meetups or networking events. Attend those events. Perhaps they have their own social networking groups online. Join those groups. When attending the events or participating in these online groups, remember to connect with people and develop relationships before trying to sell your services.