I'll be up the canyon that week camping more than likely. I have a sour fest ticket but may just sell it. I'm really jonesing to get up in the mountains.
That being said, SourFest would be an option for Saturday if you felt like it. Finding tickets on the secondary market isn't terribly difficult. Like I said, I may have one. The fest is in the afternoon so you can definitely still do stuff afterwards considering the pours and ABVs are small.
The Fort Collins spots are all pretty straight forward. Funkwerks, Fort Collins Brewing, Odell, and New Belgium are all basically on the same street (Lincoln, New Belgium is just north of Lincoln you can't miss it). Funkwerks usually has a small food cart that serves hamburgers and stuff. Fort Collins Brewing has a restaurant attached. Odell will have one or two food trucks. The Goodness is usually there and is a tasty combo of basic American stuff with some vegetarian options. New Belgium has a couple trucks around as well.
If you want to do the New Belgium tour, which I highly recommend, just show up when they open and get on the list. The tours are always booked 3 months out, but you should be able to catch on as people always flake out.
Then in old town you have Coopersmiths and Equinox. Coopersmiths is a brew pub with decent beer and good food. Equinox is a hippy-ish joint. The beer is good but it gets crowded and loud sometimes. Black Bottle Brewing is just South of old town on Prospect. They have some good beers of many varieties including barrel aged stuff. They also have guest taps and serve decent food. Lastly, there's a new brewery named Horse and Dragon. Haven't been there.
Beer bars/restaurants in Fort Collins are The Mayor of Oldtown, Choice City Deli, Tap and Handle, The Forge, and Mainline. The Mayor has 100 taps and is a really fun place. You won't find a ton of rares, but there's plenty of great beer. They also have a kitchen that serves sausages and pub food. Choice City is the ****. Can't miss. Get a burger or a rueben. You'll be blown away by the quality of beer on tap for a butchers shop. Tap and Handle is right across Olive from Choice City. They have 50 or so taps. The Forge is a cool little place. They only have 10 or so taps but they're usually good. It's impossible to find so don't be afraid to call. They don't have food other than charcuterie. Mainline is a restaurant owned by Breckenridge Brewing and Wynkoop. You'll find their beers there. The food is good and it's a decent place to watch a game if needed (so is old Chicago right next door).
If you want to shop go to Wilburs, Supermarket Liquor, 287 Wine and Spirits, or Pringles.
Verboten and Grimm Brothers are good spots to stop in Loveland on your way up. Liquor Mart is a good shop in Loveland.
Some under the radar spots I've been to recently outside the Denver area would be The Post in Lafayette and Bru in Boulder. The Post has the best fried chicken I've ever had. Their beers are coming along. Same thing with Bru. Amazing food and good beer.