The Government finances

I was wondering if anyone has a detailed breakdown of gov spending per department etc. A large spreadsheet type thing . Maybe someone good with software could make a little programme where people can change variables in economy and amounts spent and taxes raised that will allow people to see what certain changes will make to the overall picture . A bit like a department of finance simulator. Then we could get every party to say what exactly they would do with the variables and show them to us on the programme/simulator.