How easy is it to put a login/password feature to sell memberships on a site that I would like to create, so that each customer can have their own custom profile membership using adobe business catalyst? Is it possible? If it is, is there a tutorial of some sort to be able to walk me through it?
You can create secure zone and sell membership , after seting up secure zone insert login in the page thorugh site modules.
For customer profiles, you can use web apps and create profiles. Customer would login and then can update the details.
Above links should help.