Two things you can do to try and recover your data (depending on what
sort of data it is):
0) Unmount your filesystem with these deleted files immediately. If
you have not already done so, the chances of you recovering them
is getting smaller all the time. This might mean booting from
a CD instead of the disk if it is your root filesystem.
1) run "strings /dev/hdX | less" on your disk and search for bits of
your text documents in the output, then cut-n-paste it to another
file ON ANOTHER FILESYSTEM. You _could_ just dump the output into
a DIFFERENT filesystem, but it could be pretty large, so you may
want to find the actual data first before doing this. If you have
a small number of deleted text (or text-containing) documents to
which you know some of the expected content, this may work.
2) (much more complex) If you haven't also deleted the directory in
which these files resided that is a big help. Do "ls -id /dir"
on the directory in which the deleted files lived. Then run
"dumpe2fs /dev/hdX" to find out which group this directory inode
lives in. You will also get a listing of free blocks for that
group. For each free block in that group do (blocksize as reported
at the beginning of debugfs output, probably 4096):