I bit furthur. I go to Scotts in Westchester. Continue up 55 to 294, North on 294 to Ogden. Then just another 3 mins. I would guess 30 mins more. There are others that are a bit better, but it is at least easy as far as Chicago goes. Use mapquest for exact details or let me know and I can help you out.
There's a new one in Tinley Park that's phenomenal. It's probably 25-30 minutes east on I-80 from Joliet, depending on what side of town you're on. The store is called Aquatica, and it's in a strip mall on the NE corner of 167th & Oak Park Ave. in Tinley Park.