The best way to learn about beer (or wine) is to go to tastings, or to go to places where it's taken very seriously.
I'm a newbie to savoring craft beers. While I was lucky to be exposed to different beer styles in France, Belgium and Germany in my 20s, I tended to drink lawn-mowing beers until very recently. Part of this is economic, but part was also the fear that I wouldn't like what I ordered and I'd have to drink it anyways (cuz that's just how I am).
So, attending beer festivals is a good way to being exposed to new and different styles of beer, and new brewers—however, they tend to be too busy to get real good information about what you're drinking.
You have to watch for beer tastings, but it's worth your while.A beer tasting is an organized event that usually features one craft brewer or one style of craft beer. John Foyston of the Oregonian frequently mentions them in his Brew News column in the A&E. We try to post about them here as well.
Places that offer beer tastings include La Bodega, Belmont Station, Liquid Solutions, and Woodstock Wine and Deli. There are other beer related events that happen elsewhere, like local beer luminary Fred Eckhardt's beer pairings with cheese or chocolate, or brewer's dinners at various restaurants around town.
There are just a few places where craft brews are taken very seriously, and where there are enough different beers to make it worth your while.My favorite, and certainly where I've learned just about everything I know is at Concordia Ale House. They tend to have really interesting things on tap, and a huge collection of bottled beers. The staff are well educated, and especially when it isn't busy, are happy to share tasters and information. Just reading their draftlist is an education! Other places that have good beer on tap and well-trained staffs include HorseBrass, Rose and Raindrop, and Oaks Bottom. La Bodega is an excellent place to explore bottled beers, (they have quite a few, and they are true beer geeks about the storage) and it's a small enough place that you can really get some special attention if you'd like that. And Henry's Tavern downtown has 100 taps, and is excellent—but only if you sit at the bar. The waitrons are clueless about alcohol.
Be sure to ask questions, and tell them what you like. You'll find that many barkeeps, restaurant managers, and the like will be sure to send something special your way.
But what if you're starting, really, at a beer festival? You just need to do your homework.If you have some time before the festival, look at the list of brewers and beers offered. These are usually listed in the program or on the festival's web site.
You can learn a lot about a brewery by checking out their web site. For example, Dogfish Head pushes everything to an extreme. Is that good? Depends on what you like (I love some of their stuff and hate others).
A site like Rate Beer (ratebeer.com) can be helpful in determining what you might like. Look up a beer you like, and then a beer that looks interesting. Admittedly, the site isn't as easy as it could be to use, but, it can be helpful.
Trust your intuition.Have you ever noticed some beers in the grocery store that have no information about the brewery? Isn't that odd? It seems like the big local breweries' packaging is full of personality. So what are you to think of a, say, Blue Moon, or a Green Valley? Surprise, surprise, Blue Moon is owned by and brewed by Coors. Green Valley is just a nicer name for Anheuser-Busch.
Of course, the same can be said of Session, though it does actually say in the fine print that it's brewed by Full Sail.
There are smaller names whose brewery names I'm blocking out, but they're easy to spot at the grocery: they're craft brews, and they're cheap. Usually, they're cheap because they aren't consistent, or just aren't so good. Your mileage, of course, may vary. They might be contract brewed, they might be brewed by a bigger macrobrewery. Who knows? Just remember, you get what you pay for.