That's the best advice really, go to a music store. Find one which is comfortable for your size. Usually staff in those places are helpful and know what they're talking about. When I bought a guitar I asked a staff member to give us a little concert with a couple of different guitars so I could choose based on how they sound in the hands of somebody competent.
Whilst they don't really do 'beginner' guitars you can certainly get solid ones for the lower price point, you obviously don't want to go in too deep considering most people pack up learning within the first 6 months.
You might already know this but I will say that a lot of the cheaper guitars come with crap amps, as soon as you're serious about learning you'll probably need to upgrade.