BuildingPackageKitFromSource

1. git clone git://anongit.freedesktop.org/git/packagekit/PackageKit
2. cd PackageKit
3. git pull
4. mkdir ~/.root
5. yum -y install glib2-devel dbus-devel dbus-glib-devel pam-devel libX11-devel libsexy-devel xmlto sqlite-devel NetworkManager-glib-devel PolicyKit-devel libtool docbook-utils gnome-doc-utils python-devel perl(XML::Parser) intltool gettext xulrunner-devel libarchive-devel gstreamer-devel gstreamer-plugins-base-devel qt4-devel cppunit-devel pango-devel fontconfig-devel
6. ./autogen.sh --enable-maintainer-mode --enable-gtk-doc --prefix=~/.root --enable-yum --enable-yum2 --enable-dummy --enable-docbook-docs --enable-tests --enable-developer --enable-local --with-default-backend=yum
7. make && make install
8. cd src
9. sudo ./run-pk.sh yum

(in another tab)

1. cd PackageKit
2. cd client
3. ./pkcon search name git

For gnome-packagekit

1. git clone git://people.freedesktop.org/~hughsient/gnome-packagekit
2. cd gnome-packagekit
3. mkdir ~/.root
4. yum -y install libgnomeui-devel libglade2-devel libwnck-devel dbus-devel libnotify-devel gnome-panel-devel scrollkeeper gnome-doc-utils desktop-file-utils gettext libtool cairo-devel startup-notification-devel perl(XML::Parser) gnome-doc-utils gnome-menus-devel libsexy-devel PackageKit-devel PolicyKit-gnome-devel unique-devel intltool xorg-x11-proto-devel fontconfig-devel
5. ./autogen.sh --prefix=/home/hughsie/.root --enable-tests --enable-gtk-doc
6. make && make install
7. cd src
8. killall gpk-update-icon
9. ./gpk-update-icon -v

In another tab:

1. cd src
2. ./gpk-application -v

Any problems, please send a message to the mailing list: http://lists.freedesktop.org/mailman/listinfo/packagekit