Hi D.,
I checked that you are from Olathe, I am in Lenexa, so I guess we register in the same place, we have 2 sailboats and several windsurf boards and I register them all at the same place in 95th and Lackman (on 95th a little to the west of Lackman) in the Park and wildlife recreation office.
Here is the link:
http://kdwp.state.ks.us/news/Boating/Registering-Your-Boat
You don't need to go to Topeka:)
OK, I couldn't find the exact address, but I found the regional office info in Topeka, I would say, give them a call and ask them.
Here:Region 2 Office
Contact Information
300 SW Wanamaker Road
Topeka, KS 66606
Phone ###-###-####
Good luck and enjoy your sailing/boating:)