One of the problems-opportunities in commercial real estate is that no one really has "all" the information. In residential real estate www.realtor.com does have all listings, but other sites may add better marketing.
In commercial real estate there are a couple sites used by commercial brokers:
CIMLS seems like a decent site and searchable by city: Browse Popular Cities: Indianapolis Evansville Elkhart Mishawaka Merrillville Jeffersonville South Bend New Albany Columbus Lafayette Richmond Newburgh Greenwood Fishers Muncie Clarksville Crown Point Carmel Noblesville Plainfield
Loop Net also searches well and is used by many commercial brokers: (Here are just the listing by city and town under the A's)