well you can start a commerce/financial society if there's none around. however there's heaps of responsibility including organisational and financial stuff which can be a burden. i think you also need some support from the uts union but don't quote me on that. but if you can manage and handle everything in the end then that's fantastic!
i'm surprised there's lots of computing/IT societies whereas there's not many business/commerce/financial related societies even though there's heaps of students in the business faculty.
i think the most relevent societies are AIESEC, International Association of Business Communicators, AYBC (Asia/Aust youth Business Council) and 'Entrepeneurs'. not sure what the latter is about.
edit: i dunno if AIESEC and the AYBC are relevent to finance orgs but ask clubs at oweek for more info.