I haven’t seen the Femme Nikita TV show, and it doesn’t appear to be running on any cable network at present (please let us know if you’re aware that it is), but as Hunter points out, it is available on DVD. You can learn more about the DVD releases here, and as Hunter notes, you can rent the show from Netflix or your local video store.
Personally, I’m going to check it out. I greatly enjoyed the American film version, Point of No Return, starring Bridget Fonda (an excellent and sadly underrated actress), and the original French version written and directed by Luc Besson.
In addition, an interesting item at the "Hollywood Jesus" website sees some serious and evocative religious allusions in the film. The author claims that the original Besson film and the American remake include explicit Christian imagery and some instances of allegory. The page includes still shots from the films to make its case, which is a strong one. This makes me want to see the two film versions again.