virt-p2v converts physical machines to run on KVM. virt-v2v converts virtual machines from Xen and VMware hypervisors to run on KVM.
Both tools were written by Matthew Booth and Richard Jones. Watch Matt demonstrating them at the Red Hat Summit 2011.
virt-p2v and virt-v2v are part of libguestfs (since mid 2014).
See http://libguestfs.org for
links to source tarballs and the git repository. The source can be
found in the
v2v subdirectories of the libguestfs source.
For the moment you can get binaries of the virt-v2v conversion server appliance and virt-p2v ISO. The appliance contains everything you need to run virt-v2v. Just boot it as a virtual machine and follow the instructions.
If you have a Red Hat OpenStack subscription, you can get a virt-v2v package from RHN.
There are preview packages of virt-v2v for RHEL 7.2 available. See this email and this email for details.
If you need libguestfs-winsupport (for converting Windows guests) use this repository.
virt-v2v ships in Fedora ≥ 21 and Debian 8 (jessie).
The main documentation is in the man page. There is also some documentation available in the Red Hat V2V Guide.
Ask questions on the libguestfs mailing list.