I know what you mean about freelance websites. It's challenging to find creative people for low compensation. A college-level marketing intern would be my first shot for your needs. Perhaps reach out to volunteer networks to see who might be available. Maybe you can source someone through a corporate sponsor. If you can find young talent, or an experienced person just starting out in their own business, they might be willing to help. Good luck!

Your outreach is highly dependent upon your type(s) of clients; B2B, B2C, and what type of products. Large segments of your clientele and prospects likely have a common type of psycho / demographics and behaviors. If you've identified those traits (sets of traits), there are oodles of resources to get your message in front of them through Social Media Marketing (SMM - influencers, bloggers, Facebook, LinkedIn, etc.), Search Engine Marketing (SEM - Google, Yahoo, Bing, etc.), and EFFECTIVE direct mail (funnels) with lead magnet and call-to-action. Once you define your goal, you can zero in on the right multi-pronged approach. Start with a small (inexpensive test) batch. Measure results. Tweak. Repeat in an endless loop until you achieve an acceptable conversion rate.