At least for games. There two legal ways to distribute games for the PSP. The first is via a UMD, which fits into the slot on the back, and the second is making a flash game that will run in the web browser. All the other methods tend to involve something either illegal or at least legally questionable methods.
Music shouldn't be a real problem. Any CDs you have, you could rip to MP3, put on a memory stick, and use with your PSP. You should also be able to play AAC files from Apple's iTunes with some of the more recent firmware releases. I'm not aware of any music sites specifically targeting the PSP, and considering how badly the PSP movie idea flopped, I doubt there would be any left if they existed in the first place.
So unless some site is talking about a Netflix style mail order game rental system, or they deal in flash games, it's not legal, free or subscription based.
Also, Cnet, like almost every other major company, subcontracts its advertising. No one at Cnet is personally verifying every place that advertises on their site. However, if you pop over to the forum feedback forum here, and mention these ads there, someone may or may not get around to looking into it. Probably depends on how long the person has been working for Cnet. If they're new, and still eager to please, chances are good. If they're a seasoned veteran, with the will to live completely beaten out of them, you're on your own.
I have seen recent ads and websites that either require subscriptions or are free. Can anyone honestly recommend a current site? I don't mind paying a fee if the site is legit and truly offers what it states with minimal problems. Seems as though some of the sites advertised on CNET are either inter-related or bogus. Please advise.

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