"Around Brussels/Brugge in 80 Beers" - I bought the Brussels version before our trip and its perfect for traveling without a tour group.Yep, great book. There should be a new edition (of the Brussels version) coming out this fall. There are some fantastic bars that have opened since the last one, not to mention a few new noteworthy beers.
Also just released is this: http://www.amazon.com/Good-Beer-Guide-Belgium-Webb/dp/1852493119/ref=sr_1_1?ie=UTF8&qid=1400828407&sr=8-1&keywords=good+beer+guide+belgium
My copy has yet to be broken in, but I also have the previous edition which is well used.
I don't get to Brugge often, but I always end up at http://www.cambrinus.eu/default.htm
For specifics on Brussels, all of kylekohlmorgen's suggestions are excellent. He mentioned Bia Mara. Good place, but the parent company has recently opened a bar at Place Flagey called The Black Sheep (https://www.facebook.com/TheBlackSheepBrussels). Also great fish-n-chips, better beer selection. The beer list keeps getting stronger. I celebrated my 40th there last week :-)
I'll stop myself now, 'cause I could just keep going. Feel free to PM me at anytime.