Recommendations on a CRM for managing Leads?

[Shaun J.]

Hey Everyone, 

I find that while I am D4D I am writing down my potential leads on a pad, or a blank envelope etc. I get home, do my research and skip trace, then send them a yellow letter (I hate cold calling or getting cold called). I make checks next to the handwritten addresses etc when I send a letter or a big circle of something that seems good but needs a trip down to the town for more research etc. 

To my question, it's quickly getting out of hand, especially since I have another person also D4D and dropping me handwritten leads. 

Can anyone reccomend a free/cheap CRM that will help me with entering leads, creating follow up schedules etc? 

Thanks in Advance. 

Shaun, Long Island NY