Just upgraded my Nikon D100 with a D5000. Now PSCS3 will not reconize my raw images.Is there anything I can do other than spend money on a new version on PS?
There is not, nor will there ever be, a version of Camera Raw for CS3 that will open your Nikon NEF files directly. It will be necessary for you to download the latest DNG converter and create DNG (Digital Negative) copies of your raw files. Then you will be able to open those DNG files with ACR in Photoshop CS3. The last version of camera raw that was created for Photoshop CS3 was version 4.6.