Try to get the backup of the PC if you don't have one of the database itself. If there are no backups available, things look grim. Perhaps DB2 puts the files of the dropped database in the trash can of Windows?
If not, you could try to recover the deleted files with some kind of UNDO tool. I remember there were several of them available in the old win 3.1 time, but thats's a long time ago. I wouldn't use that PC too much to prevent the accidential overwrite of those precious deleted files.
With kind regards . . . . . SQL Server 2000/2005/2012
Grabel's Law: 2 is not equal to 3 -- not even for very large values of 2. Pat Phelan's Law: 2 very definitely CAN equal 3 -- in at least two programming languages