Collecting and keeping accurate details of members and other contacts can be challenging let alone keeping those details current.
A good member management system should also enable members to update their own contact details in a secure environment.
A good member management system should incorporate a customer relationship management system (CRM). This can identify groups of contacts with common characteristics so communications can be tailored for those particular groups.
There are numerous online subscription CRM systems available.
Mailchimp
For the record, I have no direct or indirect interest in Mailchimp. Mailchimp is free for 2,000 contacts and 10,000 email sends per month. It includes a CRM system and allows contacts to update their own details. It can be integrated into your website and your Facebook page. The forms to collect information are flexible and hidden fields can be included so you can add your own information about particular contacts.
I can help you set up Mailchimp or optimise your existing Mailchimp account. I can also help with other CRM systems you may be using.