I'm inquiring to see what remote or even in house teams are using to manage contacts, teams, etc. I am looking into Intranets.com for my team of 5 - does anyone use something similiar? I really like Netsuite, but it is too pricey for me. Are there any open source programs?

I need to:
- manage contacts
- be able to add notes
- user logins
- calenders
- notes on specific contacts

I will have ~5 users on the system, all booking agents for a music company. Any ideas?