Okay, uhmm somewhere at the end of a hall there is a three-splitting to the left you have a save sphere, in front you have broken thingy's and stuff and a little chest, go check it, and to the left there is a half open broken door with an Al Bhed book in it.
What you have to do is when in the main hall you start a little further so walk back a bit and you see a door to the left, go in and you'll have to fight two Chimaera's then there you'll find the Al Bhed Primer XX <img src="/images/graemlins/smile.gif" alt="" /> if it's too confusing I'll have to check it again and make it more clear for you.
