cat /proc/mdstat or
mdadm --monitor --mail=root@localhost --delay=1800 /dev/md?This is the normal way to check the status of software RAID in Linux.
Check
http://www.prefetch.net/articles/linuxsoftwareraid.html, maybe is what you need.
About showing that info on Web GUI, maybe you can tweak the status.cgi page.
Btw, how do you enable RAID on endian, there is some option at install?