Google Contacts - Google Contacts is Google's contact management tool that is available in its free email service Gmail, as a standalone service, and as a part of Google's business-oriented suite of web apps Google Apps.
Dux Soup - Dux-Soup is a lead generation tool for LinkedIn.
Free Address Book - In our contact management software you can store fast and easily name, phone numbers, birthdays, address, company name, city, mobile numbers, insurance and loan info, e-mail addresses.
CloudSponge - Companies from every industry use CloudSponge’s Contact Picker to get access to their users’ address books.
Clearbit - Clearbit provides Business Intelligence APIs
BuzzBuilder - BuzzBuilder is a web-based lead generation tool that manages targeted email marketing campaigns and generates B2B sales leads.