Mounting Linux LVM partation

Hey guys,
can any one tell me how to mount my linux lvm partation,

as i installed FC3 nd gived option use complete HDD,
so it hv parted itself in lvm which is not useable now,

I hv somehw also lost it`s boot loder & now i m not able to reinstall it
i used as given in trips here,
but it`s giving error as block or device does not exists(i used
chroot /mnt/sysimage
grub-install /dev/hda)
my linux is install on HDB

so can u tell me hw to get that partation in use,

I hv Debian in second HDD(complete)
so hw can i add FC3 in grub option nd hw can i mount that portation