Magento

There is an Unofficial API at http://www.magento-blog.net/api/index.html. It has helped me out a lot.

Forgot to mention, to get to a list of all class members (functions, constants, etc) for the entire Magento basic installation, choose the class tab from the centre area (not the sidebar - the sidebar is confusing). After you click on the ‘class’ tab click on ‘class members’ then you will get three tabs ‘all’, ‘functions’, ‘variables’. Click on one of those to see the sitewide list.