I'll take this in a different direction. While sites like HubPages, Squidoo, and Yahoo! Contributor Network are all "trusted" money making sites, they're not necessarily the best. They all offer you a chance to earn money, and surely you can earn a decent amount at any of them if you work hard.
However, a better thing to think about is the underlying program that is monetizing what you're writing. For example, HubPages is mostly monetized by CPM ads (although you can include Amazon modules as well). Squidoo, on the other hand, is mostly monetized by affiliate links to things like Amazon and eBay.
Google AdSense is a great and trusted program. If you drive enough traffic to a site to generate clicks, you'll earn money, and you can rest assured you'll get paid. However, some niches are "worth" more because advertisers are more willing to pay for those clicks. So this works much better for commercial niches where people are advertising products.
Amazon Associates is another very trusted and profitable program. If you are writing about something that can drive people to Amazon, you can make a very hefty sum of money.
Finally, there are "affiliate networks" that open up many other advertisers to you. Commission Junction and Google Affiliate Network are two big, reputable names. These often involve driving traffic to an advertiser, and you're paid when people sign up for a service or order a product. It requires more targeted traffic, but it can be far more profitable than AdSense or other ads if it's done right.