my suggetion is go with WhyPark.com , 99.95 one time payment, you can have 100 websites, and most anyone can make a site in less that 20 minutes, it guides you right through the process No coding needed, preferably use adsense or yahoo publisher on your sites there, no revenue sharing, you get all the earning from your clicks.
right whypark.com is the best way for you to develop your website, it is not the parking site, you can add your own advertising code in it and you can change the site as well, it can save you lot of the time to create a website.
i read it as you already have websites and are looking for the best advertisers - correct?
Google adsense of course, then there are many second tier choices after that. Also be sure to smartly include advertisers like Amazon or CPA from CJ.com and the like as well. I find you have to constantly tweak and change CPA ads but when you hit one that works, they work very well.
If it as the others suspect - don't bother with the duplicate content garbage websites. They look like trash, people respond to them as such and sooner or later google will enforce its already stated policy of banning made for adsense websites and accounts - aka - duplicate content websites like ppc-sites.com.
I still have a few duplicate content websites myself - compared to my original content minisites there is little comparison in search engine rankings, CTR and natural linking and bookmarking. Spend more - you get more. Spend $10 - you get $10 worth in return.
I checked them .. Upload , Download , Forums websites ..
Your websites still new .. some of them not working yet , so i dont think CJ & amazon will be a good idea for now.
The best way to earn from your website would be AdSense for sure ..
You still have some alternate networks to work with like ( YPN , AdBrite ) , but i recommend to work with AdSense first.
About your upload website .. Most of big upload services like ( MegaUpload , zShare , Uploading , etc .. ) work with AdBrite from along time.
True, i think Google will sooner or later implement their policy against duplicate content. What will be the alternative for that then? say now, I'm running most of my sites with whypark.com, and to write my own content, it will be alot of time and writing, not feasible i think.