I have been looking to find some reading material on why certain fabric weaves are used in certain applications, like why use a 2x2 vs a 4x4, why use certain sizes of spread tow in some applications, etc. 

Is there anywhere that I can start to get more info on material selection and the advantages/ disadvantages in situations?

Thanks!

Yeh, pretty much this ^

There's also some technical advantages of say a 4x4 twill vs a 2x2 twill in that the 4x4 will have less crimp, theoretically giving you a stronger laminate. Same is true of a 5HS or 8HS satin weaves vs twill/plain weaves. Real world, if that's the sort of detail you are paying attention to, then you are likely also using lasers for fibre orientation and other such high-tech methods to ensure absolute optimum performance. At the hobby level, it's not something you really need to concern yourself with.