How do I shop for a guitar?

As a beginner, I was wondering how someone normally shops for a guitar? Presuming that you walk into a guitar store with no pre-concieved ideas about what you want to buy, where would you start? The last time I was in a store, a lot of the customers walked in, grabbed one of the guitars from the wall display, plugged it into an amp and some effects pedals, and played away. Is that how it's normally done? It would make sense to me to try many brands and models to see what "felt" right and sounded right to me. Obviously, as a beginner, I wouldn't be looking at any really high-end guitars, but I think it also needs to be professional-duty.

For now, I'm learning to play on a Washburn X-Series solid-body electric and always through the humbucker pickup. I have no complaints with it, but I am curious what some other guitars might offer me.