Inserting Dynamic Text/HTML into a Paragraph

Hi all! Im back :P
(anyways :P)
Ive been trying to get this stupid javascript working for the past 20 hours but I cant seem to figure it out. (not literally 20 hours, but oh well :D).
First off, heres the URL: http://68.185.139.62/Test/gallery.php
(Im working on the javascript first, I know it doesnt show right with IE...)
When you click a thumbnail on the left, it is supposed to change the image on the right, and the contents of the p (_idesc), and the h1 (_ititle). I cant figure out the right javascript to use to change the innertext though. Ive tried _idesc.innerHTML="whatever" but that never works...

Any help??? :confused:

okay i made the neccessary changes, only problem is its not displaying two out of the 4 images im not sure why it may be a server issue on ur side, but attached is a zip file with your page, i added the function that writes the image and the description into the proper places u will see this function above the head tags, i also made it to where u can use the functions over again as neccessary

document.getElementById('_idesc').innerHTML

Oh wow thanks alot! :) BTW, the two images arent displaying becuase they are REALLY big files (the images they display are just thumbnails)...

BTW, I actually tried document.getElementByID("_idesc").innerHTML and that never worked for me... In the javascript console (In firefox) it sayed that _idesc didnt have any properties... :confused:

Update:
And it works :)

lowercase Id in document.getElementById