I just launched my start-up www.zaloot.com.
It's a completely free odd-job marketplace. The way it works is users post jobs and take bids. Both employers and employees get rated and reviewed after each job. Higher ratings and better reviews should mean more money for employees and less cost for employers.
Our plan is to essentially begin by leaving it open to all users, but focusing our energy on our area (NY/NJ). We hired an SEO company that will begin work in September to do a local campaign for that area. We'll be walking around introducing ourselves to local businesses and communities.
Any suggestions? My research on here showed that there's been a few posts on building a two-sided marketplace, but none really answered these questions, if I missed them, my apologies, please link them.
Thanks