As far as I know is there no gui to set up a RAID1. And you can set up a daemon which sends you an email when there is as problem with the raid configuration.
It's not very difficult there are a few things you need to know in advance. Your OS and version,
your bootloader (lilo, grub or grub2 or another one) Do you have other OS's on the disk. How is your disk partitioned with GPT or MBR. And how many partitions do you have.
The install itself is simple you create the raid with one member missing put a filesystem on it, copie the OS from the old disk to the new raid config and make it bootable. Boot from it and add the old OS disk to the raid array.