Something similar to Black-Eye Susans?

White Daisies are a very similarly shaped flower, white with yellow centers.

Coneflowers?

ugly seed pod and no petals. Plus I'm told they're more wildflower...they scatter.

Echinacea purpurea. It comes in many other flavors, too (white, yellow, pink, orange, even double-petalled varieties).

Rudbeckia hirta (Black-eyed Susan, Gloriosa Daisy, Yellow Ox-eye Daisy) comes in a lot of different flavors, too. Some cultivars to searh for are: 'Prairie Sun', 'Chim Chiminee', 'Cherokee Sunset', to name only a couple.

What colors are you actually looking for. And, by 'similar to', are you wanting "daisy" shaped flowers? Flowers stalks that terminate in a single blossom? Do you mean, specifically, wildflowers? Is there a reason that Rudbeckia or Echinacea won't suit your needs?

There's the genus Leucanthemum, or Monarda.

This should get you started.

I wouldn't mind some purples.

Actually, I meant I like the way Susans stay in their clusters. I have a couple runners, but for the most part they stay together. I don't want something that scatters all over.

Well, my friend has some reclaimed prairie with lots of Echinacea, and it's already spent...just brown seed heads.

You gave me plenty to Google. Thanks!

A lot of wildflowers fit that bill. Check the different species of Liatris. My Liatris aspera is still blooming, and the L. pycnostachya has just finished.

I'm just a bit south of you (near StL). My coneflowers (Echinacea and Ratbida) are still going strong. Deadheading helps their performance, as well as keeps the spreading down. I leave a few heads for the birds, at the end of the season. =)

You're welcome. Good luck. =)