iostat is available, but might not be installed. Try /usr/sbin/iostat, and if it's not there, ask the sysadmin about getting it. iostat gives you per-device info -- because of the way UNIX filesystems work, in general, per-process I/O statistics aren't very meaningful.
The lsof program (also maybe in /usr/sbin, or ask your sysadmin) can tell you all the files a process has open, and some info about each file. This is often very handy.