Well, the resonance of the coil is going to depend on the size, wire spacing, permiability of the core, number of turns, etc. I don't have the formula handy, but if I have time over the w/e, I'll try to look it up. By the way, coils are self-resonating, so there is no need to add capacitors or resistors.
But honestly, the variables for something like this are immense. It would be hard to get two coils to resonate at the same frequency without tuning them. I would suggest that you build two coils that are as close as possible to being identical. Then use a rf generator to 'fine tune' them. Do the tuning by changing the winding spacing. If that doesn't get you where you want to be, then add or subtract turns until you get both coils resonating at the same frequence. I think they said 9 turns spaced over 24" and running at 9.9Mhz, that would be a good place to start.
Another hint: have the experiment completely set up before tuning the coils. That will eliminate variables of near objects. Also, people walking around the experiment might change the resonance too. Control as many variables as possible.
Good Luck!