Took a quick(!) look at Levi 1976 (year I graduated high school).

The possibilities are:
1. A. stellata
2. A. venusta
3. A. cherokee
4. A. marion

Venusta is highly unlikely because venusta has a longer abdomen proportion (1.5 times width) and distribution is predominantly Florida and east coast.

Marion we can rule out because marion is larger (10-16mm) and with marion the median anterior tubercle does not project above carapace.

Cherokee appears slightly wider in the anterior region of abdomen (vs. stellata, which appears wider in the mid-region); stellata shows a more distinctive "arrow mark" in the anterior tubercle region; Levi shows depicts the head region of stellata set further back beneath the abdomen than he does for cherokee.

To know for certain, you will need a close-up of the scape. You have some images of the genital area, but I can't make out a scape at all. Perhaps I'm just not seeing it? Levi writes that mature females have been found "in central and northern states" from May to November.

Judging on appearances, I would say A. stellata. Perhaps someone who has looked at enough of these would immediately know. At least you should be able to get by with Acanthapeira cf. stellata, I think.

Levi's article is interesting reading (as always). It can be found here:
http://ia341003.us.archive.org/2/items/bulletinofmuseum147harv/ (large file)

-Kevin

I have just uploaded a series of images of what I think is Acanthepeira cherokee here. I added the second image of the epigynal area of this alleged A. stellata in anticipation of a comparision of it with the alleged A. cherokee. As you noted the venter of this creature is strange! I hope some expert can shed some light on it. I unfortunately did not preserve the specimen.
I was fairly certain that this was A. stellata, even without good genitalia information, but I hoped to reopen a discussion. Your input has certainly justified my hope!
Gayle