If you need professional quality stuff, you should be paying for it from one of the many stock agencies around. The agencies have lots of rules and safeguards that are designed to save you the headache of worrying about whether model releases were signed, etc.
Also, photographers with GOOD images don't sell them for $0.05 on Fotolia, Dreamstime, etc... Getty Images sucks because of it's restrictions and $3,000 / price tag and prehistoric policies. If you check the stock photo site's payout rates you'll realize why they have so many generic images and so little amazing photography. The good photographers keep their stuff off those stock sites.