Job Interviews - The Wage Question

This question is for a graphic/web designer who knows they’re good, and has had a few good, well-paying jobs.

Basically, do you (and if so how) ask what sort of wage you’d be getting when employed by the business?

Do you ask straight out what they’d be paying you, or is it impolite or something? To me it seems like a pretty reasonable question, but one that seems to be steered away from when nervous…

Is it a question you’d ask straight away or towards the end of the interview or what? How does it usually work? lol…