GUID issue?

I installed this plugin and it was working great, but after I had to move the site to a new domain, I’ve had issues with the links within the plugin pointing to the old domain (and subsequently the user ends up on the old domain)…

I checked the php files, and it looks like everything is referring to a post GUID… example:
<td class=”lostfound lfitem” >
guid; ?>&action=claim&item=<?PHP echo $item->id ?>” class=”lostfound lfitem”>Click here to claim this item.</td>

Is there anyway to update this plugin to point towards my new domain? I tried deleting the plugin and reinstalling it, but it still has the same issue. I also tried manually putting the new url into where the PHP echo statement was, but that just threw me a 404 error. I would try to update the GUID in the database, but…

http://codex.wordpress.org/Changing_The_Site_URL#Important_GUID_Note

Any help would be appreciated, please and thank you!

http://wordpress.org/extend/plugins/the-lost-and-found/