IPC is short for inter-process communication and is no standard file in your installation or environment but rather a domain socket.
After you installed
geth the ipc socket is not automatically created and its also not considerable a permanent resource.
geth.ipc socket only exists as long as
geth is running. You can specify the ipc path with the
--ipcpath "/path/to/my/geth.ipc" flag. You can control the available apis with the
--ipcapi flag. You can disable IPC with
--ipcdisable Disable the IPC-RPC server
--ipcapi "admin,eth,debug,miner,net,shh,txpool,personal,web3" API's offered over the IPC-RPC interface
--ipcpath "geth.ipc" Filename for IPC socket/pipe within the datadir (explicit paths escape it)
Read more on the go-ethereum wiki on management apis.