Spice model search with advanced sorting functionality
Unfortunately, most of the IC vendors would rather provide you with a model in their proprietary simulator format than in a generic format that would allow you to co-simulate their parts with their competitors' parts. TI provides models for Tina-TI, Linear and Analog provide models for LTSpice, etc. 

Some vendors may provide models for Spice3 or PSpice, but rarely will they provide models for both.

Your options are


Learn which vendors provide PSpice models and only use their parts.
Learn enough Spice3, LTSpice, and PSpice syntax to be able to manually convert models from other formats to PSpice. This can be anything from trivial for simple models to very difficult for tricky ones.
Use each vendor's proprietary simulator to model the subcircuit using their IC, and then use good systems engineering practices to combine subcircuits and design a working system. Then verify with testing on the physical circuit.


I strongly recommend you get comfortable with option 3. At some point your designs will become complex enough it won't be reasonable to simulate the complete system in Spice, so you'll need to understand how your subcircuits interact and be able to design this way at that point anyway.