Easy Sample to create ipk files

step 1. ceate 2 new temp dirs say "_ipkg_temp" "_ipkg_tar"
step 2. use _ipkg_temp as root directory put your stuff there:
for example:
usr/bin/lala.sh
step 3. pushd _ipkg_temp; tar -czf ../ipkg_tar/data.tar.gz .; rm -rf * ; popd
step 4. create control file in _ipkg_temp
fill the following fields: (CONTROL="control")

        echo "Package: Your_package_name"   >  ${CONTROL}
        echo "Version: 0.1"             >> ${CONTROL}
        echo "Description: your_descriptions">> ${CONTROL}
        echo "Section: base"            >> ${CONTROL}
        echo "Priority: optional"       >> ${CONTROL}
        echo "Maintainer: Noname"      >> ${CONTROL}
        echo "Architecture: all"        >> ${CONTROL}
        echo "Homepage: http://ooo.xxx.vvv/svn/trunk"       >>  ${CONTROL}
        echo "Tags: group::unknown"       >> ${CONTROL}
        echo "Depends: ooxxooxx"    >> ${CONTROL}
        echo "Source: http://ooxxooxx.ooxx.vvvoo/" >>  ${CONTROL}

then tar -czf ../_ipkg_tar/control.tar.gz .
step 5. in _ipkg_tar create debian-binary file contents 2.0
echo "2.0" > debian-binary
step 6. in _ipkg_tar ar the ipkg file
ar -crf ooxx_0.1_arm.ipkg debian-binary data.tar.gz control.tar.gz

Done :-)

reference http://code.google.com/p/comic-reader/source/browse/trunk/packer/pack_eet2ipk.sh