OK, here's what I have so far, how do I make the leap to getting the rowid?

select
b.machine host,
b.username username,
b.server,
b.osuser os_user,
b.program program,
a.tablespace_name ts_name,
row_wait_file# file_nbr,
row_wait_block# block_nbr,
c.owner,
c.segment_name,
c.segment_type
from dba_data_files a,
v$session b,
dba_extents c
where b.row_wait_file# = a.file_id
and c.file_id = row_wait_file#
and row_wait_block# between c.block_id
and c.block_id + c.blocks - 1
and row_wait_file# <> 0
and type='USER';