2 FAQ questions? but i couldnt find any FAQ :/

I've got a machine with 4 harddrives. 2*100GB and 2*120GB. Running hardware raid 1 on a 3ware. That part works.

Until recently the first LVM appeared to be working, or, it does still work.
How ever, when we added the new raid1, the 2*120GB drives, we didnt get the full +120GB space. Where is it ??

The other question is:
running pvdisplay on /dev/sda5 says it is available in the PV STATUS field,
but for /dev/sdb1 it says NOT available. We did run a pvcreate on /dev/sdb1
and then vgextend. using vgdisplay, it appears to have become 100GB larger,
but if it is larger, why isnt it available ? We have tried to deactivate and activate the LVM ?

JonB