AgSquared: still in development, but you can sign up for updates. When it's launched, it promises to be great recordkeeping software for all kinds of farms.
COG-Pro: The Online Solution to Organic Record Keeping satisfies NOP requirements.
Local Harvest: The first and still the best directory of sustainable farms, markets, CSAs, etc. Get yourself listed -- you will be amazed at how many customers come your way as a result.
LocallyGrown.net: Create your own farmers market with other farmers or just yourself. Customers order online, then pick up at a set time and place.
Real Time Farms: A directory of farms, markets, local food restaurants, etc. with social networking component. Create your own business description and customers can comment, upload photos, share tips.
Community Supported Agriculture
All three of these programs allow members to sign up and pay online, eliminating a huge amount of data entry for the farmers. They also have CSA management features such as assembling picking lists, delivery maps, invoicing, sending newsletters automatically, and more. Check out and compare:
Small Farm Central: Easy-to-use templates for websites; the developer was a farmer and knows how to create good-looking, useful sites.
Good Food Jobs: you can post farming jobs, or look for jobs in sustainable food service, nonprofits, and more.