I'll echo SlukBunWalla on Sea of Marvels. I loved the store the first time I was in it, but wish Hung would stock more varied corals. It also seems like it's gone downhill a bit since the first time I went in but I do make a point of stopping by every time I'm in Iowa City (going to school in Ames) and generally buying something.
The haggle pricing generally works out fairly well for me and the more you go in, the better it works out. I've got the advantage of buying for a couple buds of mine in Ames when I come to IC as well, so I'll generally pick up a decent amount of stuff which doesn't hurt the prices I get, either.
Petland blew me away when I discovered they carried ORA frags. It's great to go in and chat with the staff who are enthusiasts and also on RC (at least in two cases that I know of). Their prices can be a bit steep in some cases, though. It doesn't help that I go to Iowa City to visit my girlfriend who tags along to the fish stores but will still give me an evil eye when I start eyeballing some of the pricier frags.
I did just pick up a 47gal column and stand there the other weekend, though, which is sitting in my room waiting on my shipment of dry fiji rock and 250w outer orbit fixture. Big sigh of relief when it passed the leak test since it's a discontinued model and Petland is a bit of a drive for me!
Pretty stoked to see the 47 display they have up front grow out, and anxious to see how the frag tank turns out. It's an attractive setup. Iowa Pet Foods in Des Moines has a sweet rimless frag tank with disappointing selection but nice 25% off sales frequently.