It looks like you lost one of your controlfiles.
1) Make backup copy of your current controlfiles (all control files!!!)
2) Copy one of the controlfiles to another one
3) Startup database
4) If it is started you are lucky
5) if not, try to restore another control file and copy it to the rest locations
6) goto 3

If you know all the redo log files and datafiles in your database you can create by hand sql script to recreate controlfiles.

Sergey.