membership list cck v user profile

I am looking to convert my current site which is a site for a local scuba diving club, from custom php mysql to Drupal. One of the main things that I am struggling to work out is how to deal with the membership database. Currently I have a separate membership and user tables as not all members access the site - but registered site users (who are also members) need to search the membership list. Also I do not want users to be able to update some of their own data (diving qualification, renewal date etc). Instinct tells me that I can create a membership list with CCK and views, but I am struggling to link this data with user account data. I have looked at modules like membership, and civiccrm, but they do not seem to be the right solution. Could anyone point me in the right direction? Thanks Alan