identification - How to identify SMD devices from the codes on top of the component?

I have a PCB and I am trying to identify a couple of the ICs and other SMD devices that are on there but can't find anything on or offline that tells me what the package codings mean.

I have a couple of pictures of the components that are of particular interest to me and if anyone could:

1. 
   

   Help identify these components and,

   
   


2. 
   

   Tell me a way I would be able to try and figure it out in the future?

   
   
   

I have tried a number of websites and none of them have really offered much help for any of these components below...

codes are: KT3 (SOT23) [top left], CVL (two pin) [bottom left], not sure of the right hand side one. Could either be 1P+backwards K, or Kd+upside down 1, or the K could be an x - it really is not clear, even under a microscope)

This is slightly clearer and is A48 I believe - no luck on this one either. I imagine it is some sort of single op-amp but again, I can find nothing.

Any help on this and a source of information for this type of question would be great!