Did you try the command:

tar czf archive.tar.gz *.doc *.xls

Options here are:

• c: Create
• z: Gzip
• f: Output file

To extract:

tar xzf archive.tar.gz

You can read the manual of the tar command for advanced options:

man tar

Is there something wrong with listing the files you'd like to add to the .tar file?

$ tar cvf some.tar file1 file2 file3

Example

$ tar cvf some.tar serveralert.log page.html
serveralert.log
page.html

You can just use

tar -cf myfile.tar /etc/dir1 /var/www/html /home/somedir

also, you could use

tar -czf myfile.tar.gz /etc/dir1 /var/www/html /home/somedir

This second example (note the z in the -czf parameter) will compress the tar file using g(z)ip.

Take a look at the --new-volume-script option, which lets you replace the prompting mechanism with a different mechanism or with a generated filename. ((tar.info)Multi-Volume Archives in the tar info page.) The problem with split is that you need to cat the pieces back together to do anything, whereas a multivolume archive should be a bit more flexible.

I'd use find, sort, xargs, and let you make the .tar file names unique on your own. Read the man pages for each, and here we go:

find . -type f -name '*.jpg' -print0 | \
sort -z | \
xargs -0 --max-args=4000 echo tar cf FIXME.tar >doit.tmp
# now, edit (`nano`, `vim`, `emacs`) the `doit.tmp` file, 
# replacing `FIXME` with 4 unique names, then
. ./doit.tmp