Wow! New members showing up left and right! Could it be that this national cold snap has folks at the 'puter instead of riding?
Welcome to the boards!
OK Tango-you asked for it, time to pay the motorcycle tax, AKA accessories!
We've been triking for 18 years, I've had a 2 wheeler of some sort for 42, so we've accumulated a few things.
So the first accessory I would get? Drink holders and a pair of good insulated cups. The Butler seems to have a very good following, but we found our own cups and got holders to fit. At least 20 oz is recommended, better if larger. Even on mild days you need to stay hydrated to keep the riding skills sharp.
As for the rest, there is stuff for you, and there is stuff for the ride, like safety chrome and other farkles, from heated liners for the cold to cool vests for the heat, chaps, jackets (leather and/or textile) helmets, (I have 2 half helmets, an open face and a full face, wife has a 1/2, a 3/4 and a modular full face.) We use the open face helmets the most. Intercom system, Mp3 player hooked into the intercom, but that may be superseded by the phone- it has 8gig of music and can get Pandora internet radio. I love the RAM mounting system - almost anything can be mounted to the bike with the balls and arms. Seating - we sprung for a custom seat, Diamond in our case. Both Gloria and I agree it is the best thing we got for the trike. We ride long, 200 miles is a short ride for us, and the stock seat just wasn't working for us. The difference in comfort was amazing and immediate, and it got better we put miles on it.
The list could go on and on.
You don't need everything at once, but it is probably a good idea to clean out a cabinet or at least a few shelves in the garage dedicated for those trike items that are coming.