My gosh, Robcobbins, you've had this request for info here in the GardenWeb companion forum for a long time! I just drifted over from veggies and such because of the ??? on the forum list.

We grow lettuce and onions throughout the vegetable garden - almost, wherever there's room, in go L & O as transplants and sets. The larger plants (esp. vines) can kind of overwhelm smaller so your experience with some of those is educational.

Below is linked a Cooperative Extension site for companion plants which informs a little on "allies and enemies" as well as those kind of tolerant relationships we think of as companions.

Steve

Here is a link that might be useful: Companion Planting