I've been enjoying the Millstream brews from the Amanas. Their spring beer, Maifest is quite tasty. HyVee still had some last week when I was there. Millstream also has their Iowa Pale Ale which is quite bitter but good.
I also enjoy the New Belgium 1554. Has a great flavor if you care for the darker varieties.
My summer go to beers have to be the Boulevards. The Pale is very drinkable with a mild hoppyness (aah the persuit of hoppyness) and the wheat is good as well. If you can find it, the Bob's 47 is fantastic. HyVee had some last fall.
Not a lot of variety here in Muscatine. The HyVee in Coralville has a great selection as well as Johns Grocery in Iowa City.