I am thinking of using AdWords to promote a pruduct page on my site. I run AdSense ads on the site, but NOT on the product page. Is it OK to run AdSense ads on sub pages or is it against TOS? Thanks.
There's no rule against using adwords for sites - or pages - that have adsense on them. What IS against the ToS is arbitrage - using adwords to get traffic to click on adsense. If it isn't obvious to Google that there is another form of monetization, you could be penalised (with a low quality score ), but in your situation, of using landing pages without adsense, I can't see any problem at all.