I *think* this should do the trick, but I'm not 100% certain as I copy/pasted and modified the code that I grabbed on another site, tho it looks fine and it seems it *should* work.
Code:
RewriteEngine On
RewriteBase /
RewriteCond %{HTTP_user_agent} http_x_psp_browser
RewriteRule ^$ http://www.google.com
This saved in the .htacces file in the site's / folder should take care to redirect PSPs to Google