I have a Lide 20 and OsX 10.8 and spent hours trying to get this to work.
I followed the post from ITSMEJULIETTE 6 posts ago and followed the link. Download the 3 packages in the correct order, they all seemed to load OK but when I went to Image Capture (through applications) it couldn't find the scanner.
So I went through Print and Scan (system preferences) and hit the + button and it found it, yeh and it worked, however the interface was a little primitive.
I then rebooted and went through Photoshop File Import SANE and a better interface surfaced. So at least it seems to work OK now, otherwise I was prepared to throw the scanner out. I've only just done this so it's early days and a rather different layout but all seems OK.
Thanks everyone