I am a former Napervillian, now I live just over the border.
Petco - Have not had any problems with FW
I have bought there, but don't rely on the staff for info. I bought my favorite predator (Sorubim Lima - Shovelnosed Cat) there and was promptly informed that it was a scavenger and loved Algae wafers. I knew better, and weened them onto frozen blood worms over live fish.
Petland - Their prices are not the best, but I've gotten to know people there and have spent a large stack of bills there. They've special ordered for me and have the best selection of plants. Their salt water section is also extensive.
Pets, Etc. - Inexperienced high school kids maintain their tanks. One guy cleaning the tanks asked another if he was supposed to vacuum the gravel after about his 5th tank. I don't recommend them anymore, they've lost a step or two.
Petsmart - Dry goods.
A Pet Paradise - 2009 W 63rd, Downers Grove - They've got a large selection, but keep all of their fish in small tanks. Never bought here before, but their selection is wide.
Critters Pet Shop - St. Charles - Just avoid it. Horrid.
Scott's Pet Shop - 3054 S Wolf Road, Westchester - Don't call them, they won't answer. Good luck getting help when it's busy. With that said, they have the biggest selection of exotics. They have jelly fish, sting rays, all kinds of stuff. Great place to even just browse.
Tropi-quatics - 426 S Main St, Lomard - If you want a new tank, this is the place. I got a new 72 gal
bowfront, glass top, strip light, solid wood stand for $400. The tanks are dirty, but if you want a new tank, look here.
Dog Patch - On Ogden in Naperville - Dirty, algae ridden tanks, I don't recommend it. But if you are in the market for birdseed, great selection.
Just a couple to wet the whistle.