I'm the 800lb gorilla in this subject. I can help. Buckle your seat belt... here we go!
NewsPaper web site banner ads and Google PPC are really apples and oranges.
NewsPaper web site banner ads (lets call them NPB's) are more branding tool that happens to create some site traffic, where as Google PPC is mostly a site traffic tool that happens to have a lil bit of branding ability.
My SUMMARY:
Go with PPC*, then, after the PPC game plan is dialed in, then I would open up a remarketing campaign, then, would I go off into branding ads (like NPBs)
DETAILS:
There is a boat load of waste in NPB's. Comparing Cost Per Click (CPC) of NPB's vs PPC's* will be an unfair fight.
#1). The vast majority of NPB's impressions go to people that are not in the market.
#2). Your NPB ad gets rotated on and off the page. Your buying impressions, not the ad position (pause and think about this). If you refresh the page, in many cases, your ad will be gone. So, this means, if your ad makes an impression to someone in market, but, the shopper can only remember that he needs to go back to the weather page to find your ad.. WTF, your ad may not be there! Not good. IMO, this is the single greatest disconnect with NPB's.
#3). In my little part of the world, comparing CPC of PPC vs NPB is not a fair fight. The CPC of NPB's are 200%-400% more expensive with a bounce rate that is easily 100% higher than PPC*.
CAUTION!
PPC has awesome ROI, but PPC spending must match your dealer profile*!!!
IMO, if I had a tight budget and a small inventory, I'd go with Google PPC ads that uses a tool that creates ads based on your inventory (i.e. Haystak or DDC's Total Control Dominator) If I had a giant inventory (or multi-franchise) I'd expand the PPC ads into more generic terms and expand my advertising geo-footprint. Only then, after my PPC game plan is dialed in, would I go off into branding ads (like NPBs)
*PPC's done right require a SMART manager that runs the PPC game plan intelligently. I've written extensively here on this topic.
HTH