you can find all SAP tcodes at <a href=”http://tcodes.ofsap.com/”>All SAP Transaction Codes</a>.
There are more than 100,000 tcodes there. It has the search function (based on tcode name, description, and its program) and shows the SAP menu path(s) for each tcode.
There are also additional information and links about the tcodes. You can also contribute by adding additional information and link of your favorite tcodes.
you may wish to look at table TSTC and TSTCA from TX SE16.