Talk2d,
You will not be able to see details of a competitors adwords or social media ppc campaign unless they invite you to become an admin on their account (or somehow you get their login credentials).
For your targeted audience question, I'm not sure what you mean exactly. Are you wondering how you configure accounts to target a specific demographic or are you wondering how to figure out who your target audience is?
If it's the former, it depends on who you are using. Features in AdWords, Facebook 7search, micorsoft adcenter and the various other PPC programs out there vary quite a bit. In general most are pretty straight forward in choosing where, when and who you want your ads shown to.
As for figuring out who your target audience is, you can go about that in different ways as well. For web design, think about what kind of clients you want to take on. Are they small businesses? Individuals? Big companies? I would focus on a niche. For example some people specialize in building websites for lawyers while others build them for wedding planners while others only work for large corporations. With web design you can really choose your market because it applies in a lot of places.
Once you have decided who to build websites for, think of who those people are and build a buyer persona. What are they like? Why would they need a website? What problems will it help them solve?
Hope that helps,
Shawn