These are all the states I've been in, as far as I know:

In addition, I've been in Ontario.
Unfortunately, I have no recollection of many of those visits, since I was only two year old at the time. Additionally, some of the states I remember were simply driven through, with barely stops for gas. Removing such states from the map, leaves us with:

create your own visited states map
When I was two, we went out east, through New York, Massachusetts, Maine, Vermont, New Hampshire and Ontario. I don't remember any of that.
When I was three, we drove to Virginia Beach, Virginia for a show my dad had. I remember that, Washington D.C. and the Cape Hatteras Lighthouse.
When I was nine, we stopped at the Arch on our way through St. Louis, on the trip to New Mexico, so I'll count Missouri, but there were no stops of interest in Oklahoma or Texas (I do have a recollection of seeing oil wells).
In addition, I've been in Ontario.
Unfortunately, I have no recollection of many of those visits, since I was only two year old at the time. Additionally, some of the states I remember were simply driven through, with barely stops for gas. Removing such states from the map, leaves us with:
create your own visited states map
When I was two, we went out east, through New York, Massachusetts, Maine, Vermont, New Hampshire and Ontario. I don't remember any of that.
When I was three, we drove to Virginia Beach, Virginia for a show my dad had. I remember that, Washington D.C. and the Cape Hatteras Lighthouse.
When I was nine, we stopped at the Arch on our way through St. Louis, on the trip to New Mexico, so I'll count Missouri, but there were no stops of interest in Oklahoma or Texas (I do have a recollection of seeing oil wells).