On my last trip to Prague I learned to call for taxis myself (on the advice of several expats). I used both AAA (tel. 1080 or 2432 2432) and ProfiTaxi (tel. 1035). IMO, this is really the only way to go by taxi in Prague as most others are mafiosa-run.

Could anyone verify that either or both of these fine outfits are still operating?? I would be most appreciative.

BTW, I can't praise these two outfits enough. If they're still operating I hope you'll consider doing business with them. They speak good English and absolutely will not rip you off. To wit, my trips from Praha 15 (near the Skalka Metro stop) to the airport were 325Kc at the time (1996-97), and that's as it should have been. I tipped generously on top of that even though it wasn't necessary.