There are a couple of antique stores right off of Exit 73 south of Sioux Falls (on the Tea exit). There is I-29 Antiques about a half mile west of I-29 and another antique store east of the interestate and is near the Sinclair truck stop (which is being remodeled). There are a couple more antique stores downtown. My recollection is that they are on the northern end of downtown as one is going to the Falls via Main Ave. Not too far from the Old Courthouse Museum and the Minnehaha Cty. Courthouse.
MJ1986, I have seen the Proud Panda, but have been by the location recently and the place has closed down unfortunately.