I am not sure exactly what there is to do and depending how early in the fall you are going it should be pretty nice with beautiful color. I noticed when we were camping a few weeks back at Sleeping bear dunes that there were a few beaches that did not allow dogs on them, mainly state land on the great lakes won't let animals.
If you can let me know where you are going exactly I'll do some searching and calling for you if you would like.
I live in Michigan and I love being farther north in the fall, the color is awesome.
You know, if you run into problems with some place for Diesel to stay, he can stay over here, I may just have to adopt that handsome guy though- hehehe!
Let me know if I can help,