Assistance needed

More a novice on CRM as I have only theoretical knowledge. An NGO I am in touch with is finding trouble in their contact management of their initiatives – like visitors to the various programs they offer related to health, sustainability etc etc, and in further using those contacts to for their other marketing initiatives and future events. The contacts are thousands as of now with more visitors coming into this list.They don't have enough money to have a CRM in place currently. What should be the solution here to sort this.

1) Are there any free CRMs that can come handy?

2) If there are no CRMs in place, what would be the best way to handle the concern?

Can anyone guide me on the same.