I strongly recommend Kingfisher woodworks bokkens. While they may be a little on the expensive side, they are extremely functional, beautiful to look at, and should last you quite a while. So if you believe you are serious, which it sounds like you are than i would stronly urge you to look into these.
Now as for Lyle's idea goes i havd tried a few red oak bokken when i started out and found them to be not so good. cracked and splintered easily. However white oak bokken are also very good, and i believe you can pick them up for about $50.00 or so. And as for the car analogy i know that not only myself but also alot of friends of mine wish our first cars were alot more reliable. Nothing like missing a first date because of a broken down car, man i thought i had a chance