You have two choices:
For Fedora, see Koji http://koji.fedoraproject.org/koji/packageinfo?packageID=14565, or if your mirror is updated, just "yum install linux-user-chroot".
Build from source
As of this writing, OSTree depends on (unreleased) GLib 2.36 and libsoup from GNOME 3.7 development. You can use use Jhbuild to build as a user.
Here's a sample ~/.jhbuildrc:
checkoutroot = '~/src' prefix = '~/build' skip = ['nss', 'libxml2', 'nspr', 'fontconfig'] moduleset = 'gnome-world-3.8' ignore_suggests = True
The ignore_suggests part is strongly recommended.
Once you have jhbuild set up:
$ jhbuild build ostree