Loop D and E are very close to lake and cell service is great. A and B are also close but no cell service.

Not that I recall

Yes and they have better cell service than the sites near the check-in office. Right on lake! Enjoy.

If your definition of "close to lake" means a short short walk or you can hit it with a thrown stone then I'd say, No. Several sites in dry Campground E should have good views. None of the campgrounds have what I would consider as direct lake access.

Campground C is mostly dry camping but most of the spaces in Campground A are a little closer. They are both pretty close to the lake.

Yes. More info at : https://azstateparks.com/alamo-lake/explore/facility-information