Here is one way to build a simulator
Others can be built with golf balls and plywood, etc... Search for it on the web.
Your board selection will be greatly affected by the balance you have. You should start by renting or trying a Start board. They are very stable and good for the initial phase of learning. If your balance is good, and since you sailed before, it is possible that you will sail it only 2 or 3 times before outgrowing the board.
If you enjoy going out in less windy conditions, a longboard would be great for you. It has a daggerboard, so you can go anywhere you want. A Go Windsurfer or a RIO could be great. I would also recommend a Kona One as it is a very versatile board.