Re: Hello from Clayton Delaware
Use a search engine to find a spoke calculator. It will tell you the length you need. Sometimes you can reuse spokes from a different sized hub by changing the lacing pattern, for example four cross instead of three cross. Lacing a wheel is tedious and daunting for the first time, but once you've done one and have some confidence it is a great feeling of accomplishment. If an old fellow like me who has a traumatic brain injury (from a lightning strike some years ago) ... if I can do it, then anyone can. Since the lightning injury I am terrible with puzzles and such. Study it some and you can do it, too. Patience. Perseverance. Success!
Someday when I grow up I will probably lose interest in toys with wheels, but until then...