During the summer there are a few to choice from. I typically go to Grandview on weekends, though I believe the North Market is open year round. There is a Whole Foods right by campus, and a Kroger in Grandview that has a decent selection of organic food. If you make friends w/ someone with a car, there is a Trader Joe's about 20 minutes away in Easton Town Center (aka giant Suburban strip mall).
As for a bike, I have a car but almost never use it because I live in Grandview right by West Campus. I am on the 84 bus line at Northwest and Chambers. There are a ton of grocery stores, fast food places, cleaners, etc in the area. You can either take the 84 to campus, just walk to west campus and take the campus buses, or ride your bike (about 15 minutes) when the weather is nice. The 84 takes you to the Lennox Town Center (PetCo, Target, Barnes&Noble, World Market, AMC movie theater, Old Navy, etc). You can also ride your bike the half mile to the Shops on Lane Ave (Whole Foods, Bed Bath & Beyond, Ann Taylor Loft, etc).
Depending on your stipend, roommates, etc, you could live in Colony Club (about 600 a month), Heritage (more expensive, not as nice, but allows pets), the Meridian (about 800-900 a month, but nicer), Drayton Court (even more expensive). I recommend looking on Craigslist or driving through though b/c there are a lot of For Rent signs in the area. Everyone that I know that lives in the area (somewhere between 5th and Lane to the West of campus) loves the location. Some apartments are nicer than others, but the convenience is amazing.