Dear Link,
This time of year there is more than adequate space available at Oxbow for everyone that would like to camp. I will be camping also. I don't believe the park accepts reservations, but this time of year, again, they are not needed. You do not need a fishing license to cast or try out a rod as long as you don't have a fly attached. There should be some early summer runs in the Sandy, so if you have the time, a one, or 3 days license may be worthwhile. Look forward to meeting you on the Sandy!
steve