Preview WordPress in plesk before domain is assigned

So I’m setting up wordpress for a business that already has a website. The plan is for me to get everything working before they point the domain at the new box. Unfortunately WordPress doesnt use relative links so when I try to preview the setup (using a moderator suite called plesk) I get the WordPress DB contents but everything else is 404ed because wordpress is looking at domainname.com/whatever.css. This also means things like links and login will be broken to until the domain is redirected to the new IP.

I figured the easy way to fix this was to go into the DB and edit all instances of “domainname.com” to the plesk preview URL (thus tricking WP into thinking it’s pointed at the right address). When I do that instead of working correctly it just forwards the browser on to whatever address I replaced the domain name with. I assumed it would prepend the temporary address on to all of its requests.

If the above is confusing let me try to clarify…

-Old website is at “domain.com” which points to the old server’s IP.

-New website & WP database (with WP) are only viewable through the admin suite called plesk.

-After setting up WP it can access the DB (on the new server) but it doesn’t see any of its other files because it is looking for them at “domain.com/whatever”

-To fix this I went into the WP database and changed all the instances of “domain.com” to “NewTempDomain.com”. I figured that this would enable WP to see its files and once the domain was officially pointed at the new server I could go back into the DB and change everything back.

-Instead of working like I thought plesk’s preview site just forwards to the main plesk desktop. If I change the info in the DB to “google.com” instead of looking for its files at google.com/filename it forwards me to google.com.

Anyone who has experience with plesk or this problem and can help would be appreciated.