The data for Playstation is fully viewable to unregistered users @ http://redump.org/discs/system/psx/
Currently there are hashes for 10,205 Discs for that system to assist you in verifying that your own backups are correct.
you can apply various filters or use the search function at the top of the page to help find the disc that you are interested in.

DAT files and cuesheets are available to download to use with your preferred file management software to assist with renaming and compressing your backups to match our naming convention.

If by 'looking for' you are under the impression that you can download the game discs here, then you are mistaken, Redump is simply a database of file hashes, cataloging optical media for many different gaming consoles and computing platforms. There are no 'ISOs' or 'ROMs' available on the site. This is a common misconception, the Redump community wouldn't still be around after so many years if that were the case.

Wiggy