Block 15 is one of the best breweries in the state, and it's bourbon month there. Solid happy hour and food too. So thats at the top. Les Caves is beer bar right next door (and owned by the Block 15 people) and always has something great ontap and a large selection of bottles for in house consumption. I've never really been a fan of Flat Tail but its happy hour food is fair priced and solid. Beer is meh to me. Some people seem to like it though. (Brewery) Sky High is a great location but again its beer has been semi-hit and miss for me. (Brewery) Mazama is average to quite good sometimes. (Brewery) 2 Towns Cidery is good if you like cider. Their winter season is out and damn good. Try their Traditions line of ciders for good traditional ciders. (Cidery) Crow Bar usually has a solid tap list. (Pizza place/Bar) Squirrels has a great burger and a usually also soild tap list. (Dive bar/cash only) The Corvallis Homebrew Supply is probably the bottle shop I would recommend. Good mix of bottles. Not the largest but well curated and good variety. Market of Choice also has a good bottle selection. University Market (or "the orange store," the building is painted beaver orange) has probably the largest selection in town but as someone who lived near it for many years, they do a terrible job at moving stock and tends to be a place where distributors dump beer that is going to be past it's sell date soon. I'd never buy anything hoppy there unless it had a date or I knew when it got there. Tends to have out of season stuff or stuff that has sat around awhile. That said, sometimes you get some gems.
And to add to Les Caves, it also has some damn good food. Their biscuits and gravy is a tradition whenever I get down there for bottle releases.
Yeah the food is always stellar. Pretzel with beer cheese and nebula mustard is always a good call too.
I would simply add this to the recommendations above... Corvalis is less than an hour drive to Eugene, where there are some outstanding beer bars and stores. IMHO, there is nothing in Corvalis that compares to the bottle and can selection at the Bier Stein, and I've yet to find a beer bar there that compares to the selection you can find at the 16 tons tap house, the tap and growler and the bier stein (again). Hell, even places like growler nation, growler guys, steel pail and growler U have an above average tap list, and then of course there are breweries/brewpubs like Ninkasi, Oakshire, Hop Valley, etc. As for Block 15, if you're in Corvalis then of course you should visit. Their limited release and barrel aged beers are truly outstanding, but I can't say I've ever been impressed by their core line-up. Their food, IMHO, is over priced and over rated (of course as you're from NY, you won't find anything in Oregon that seems overpriced to you). It's decent, and I typically end up ordering food if I'm having a few beers there, but I wouldn't go out of my way to eat there otherwise. Just my two cents. Enjoy your visit.