Hey
QEMU is really handy to try out OMAP and Versatile Express boot stuff; the Linaro QEMU version has patches (progressively being upstreamed) for OMAP support and allows emulating vexpress, overo, beaglexm and beagle boards which is a good collection already. It's based of a modern QEMU commit and contains plenty of good fixes (all on their way to mainline).
Get a tarball from: https://launchpad.net/qemu-linaro Source code at: http://git.linaro.org/gitweb?p=qemu/qemu-linaro.git%3Ba=summary git://git.linaro.org/qemu/qemu-linaro.git (This is like a regular qemu git tree or tarball; usual QEMU documentation applies.)
Binaries are available in Ubuntu and backports are in the linaro-maintainers/tools PPA.
Some QEMU HowTos are hosted on the Linaro wiki, but they are a bit specific to Linaro images and tools to manipulate them. Basically you can run a beagle xm SD image with: qemu-system-arm -M beaglexm -sd your.img (You might want to throw the serial line output directly on your terminal or disable graphics or various other things.) For vexpress, you can only boot by passing a kernel or ELF image to QEMU: qemu-system-arm -M vexpress-a9 -kernel u-boot.bin
Cheers,