Can I convert my velocity 9-speed rear road hub to bolt-on?
You could get locking skewers (e.g. pitlock) or skewers which have hex bolts (e.g. this) [obviously, having a hex key or a 15 mm wrench isn't really secure, but pitlock is more secure], if you want it for the security. But all you need to do is run down to your bike shop with your wheel+skewer and get them to match it to an appropriate solid axle in most cases if you really want a solid axle (since you didn't specify exactly which hub you have, we can't really give more details).