Don't worry, there are plenty of both Chinese and imported beers to choose from. They even have Fosters with Fosters girls walking around the bar - I refused to drink it.
The Chinese ones are generally light in colour and you can drink a lot of them. Worth giving them all a good test run. Tsing Tao, Beijing Beer & Ying something are the ones I remember.
If you buy beer in a bar it's relatively expensive (same as here), but dirt cheap in the supermarket or small non english speaking restaurants.
The word for beer is Pi Jiu - said pee-jee-oh. A glass is Bei (BAY like beijing), a bottle is Ping.
So to ask for a bottle (literally one bottle) - "Yi ping pijiu", or a "yi bei pi jiu" for a beer on tap. Just making sure you don't go thirsty.
Check out San li tun (Bar street), and there are a few beers / jazz clubs at Chouyang Park south gate (can't remember the spelling).
Have fun, I'm sure you won't go thirsty. Let me know if you'd like to know more info.