I'd already started giving DS some fruit and veggies by the time he was 4-5 months old, as well as baby white grape juice. He HATED rice cereal so that was a no go. And he was almost 6 months old when Thanksgiving rolled around and I broke out the turkey baby food. He didn't appear to have any food allergy issues.
When DS was 6 months old we were told by his doctor to give him whatever we were eating. To skip the baby food route all together if at all possible because baby food is low in fat and sodium. I still bought baby food, but doctored it with butter and salt. At daycare they ground up whatever the bigger kids were having very finely. And I would grind up some things, a lot of times it would be convenient foods such as chicken ala king, beef stew, chunky soup... And LOTS of whole milk yogurt.
Formula was still his primary meal, so we'd usually start off with his bottle and then move to the table for some solids to make sure he still got enough nutrition.