Welcome sir! The two best places I know of are the parking lot across from Boone Advent Christian Church & Cherry Dr. The church's address is:
220 W King St, Boone, NC 28607
Should be free, but fills up fast so try to get there ASAP. You can also try the parking lot aside from McKinney Alumni Center & along Clement St. The Alumni Center's address is:
553 Blowing Rock Rd, Boone, NC 28608
This one will be at least $20 but still within walking distance. Good luck!