I don't know if such a thing is available. You might have to pay for such things. You could use LTSpice for your simulations. It's free and the manufacturers provide the models.
Many semiconductor manufacturers are beginning to provide symbols/models/layout on their sites. We're currently working with Analog Devices to get their complete product library for Multisim (Electronics Workbench) online.
To download them (for free), go to www.analog.com and click on the product of interest, then Symbols and Footprints. Or the direct link: **broken link removed**
For models, you can find them on the product's information page.