It's actually a service designed for commercial realtors and researchers, but my fiancee showed me by pulling a list and I said "Hey, this is the same data I was paying SalesGenie for!" They actually generate and scrub their lists from various services to keep them updated. Thus far, I have found the data to be accurate, especially when it comes to the contact names.
I paid about $600 for an unlimited 12 month subscription. I can pull as many lists as I want nationwide, so I thought I might pull a few lists here and there for colleagues to offset the cost a bit (I even asked the service and they said they don't care).
You get business names, address, telephone, contact name, # employees, annual revenue, etc. I love it because I can pull a 1-100 mile radius from an address or zip code and filter the results for company size and industry, annual revenue, etc.
If you want me to pull a small sample, email or message me.
What are you going to charge for this info?