Here is the sitch:

Home team makes the basket. Visitors go to inbound after the make and can't get the ball in so they call timeout. Following the time out, I inform the inbounder that she may run the endline. I hand her the ball and one of her teammates steps out of bounds on the opposite side of the lane and receives a pass from the initial inbounder. Legal so far. The initial inbounder streaks down the sideline on the fly patern. She is guarded pretty well, so the NEW inbounder cannot pass the ball to her or anyone else, so she wisely calls another timeout. My question now is, when they come back after the timeout, do they have the privelege of running the baseline again to inbound or must they stay put? It ended up not mattering, but I told the girl she must stay put this time. I think I blew it. Did I blow it, or did I guess right?

I don't know if I would say you blew it, you just applied the wrong rule.

Until the ball is inbounded or a violation/foul occurs they get the baseline, no matter how many TO's they call.

That's what I was thinking after the fact. I'm glad my stupid decision didn't effect the play or even greater, the outcome of the ballgame.