Half Acre, as mentioned above, and Metropolitan Brewing are two relatively new breweries.
Both are in the Andersonville/Ravenswood area (near the Hop Leaf) and give tours. You can typically find their beers in the better bottle shops (including Whole Foods and Binny's). Metropolitan, I believe, makes only lagers.
Also, one of these two (I think Metro) is in the same building as a local boutique distillery. I can't recall the name.
I also can't recall the name of the liquor store, but at the corner of Clark and Foster (right by the Hop Leaf) there's a liquor store with a great selection of bottles.
I don't know if you can get Bell's in Colorado, but the season seems right for them to be releasing their Expedition Stout. This is a favorite of mine.
I also agree with the recommendation for Sheffield's. With the baseball season over, it shouldn't be too crowded.