How does this work if it's a php site and needs a database to view correctly?
Not a problem. Set your landing page in PHP with your DB. It makes no difference. The thing is people will search your property (or item) for sale on your page and won't find it. So they will click on what's clickable (your adsense/adbrite/or whatever CPA,etc...) and you get paid. Even better, they hopefully get back to your ad and email your with questions. Get that email, make a list and send your CPA or other to them...
The key is to make it personal.
A recent example:
I recently saw a survey where people could get $500 to make it.
My email was something like this: " Hi guys, I have a friend working for an online business. They are paid to create surveys for big companies. They charge those companies in order to have a good genuine feedback for their survey. So they give $500 for this. They only need 100 persons though. So it's not for eveyone. Also, you must have been laid off in 2010 OR 2011. Before 2010 is not good.
They already have like 30-35 persons so far but need 100, so if it's your case, you can get some cash.
Steve"
I get about $20 for each 100 emails depending of the CPA pay off.
Since 2004, I have like 35,000 emails with always a few no longer good every time though. So every month, I have about 500 new emails and each time I send an email, I have 40-50 emails that are no longer valid.