Barbara,
Hi there!
I've done some internet hunting, and it seems only 11 of the 13 episodes were ever made (and only some of those aired in the USA). Here, Sky 1 did air all 11 episodes, thankfully, but if my memory serves, not in the correct order, which is...
1 - Pilot Episode
2 - Fidelity
3 - Grievous Angels
4 - Blind Witness
5 - Nocturne
6 - Abby
7 - A Three-Hour Tour
8 - Simon Redux
9 - Last Call
10 - Seeking Asylum
11 - Nexus
The series was officially cancelled, and the cast, sets and crew disbanded in October 2002, by the network UPN (former home of "Buffy The Vampire Slayer"). Alas, the series was never completed, and a resolution of any kind never got made. (The series would probably have been concluded with "004" and "It's A Wonderful Afterlife" - which would have formed a two-episode finale, concluding some of the show's original storylines, characters and themes, but leaving enough to continue, if the show ever got recommissioned.) The chances of this show ever making it onto DVD or UK terrestrial TV is highly unlikely, because it died, both ratings-wise, and the fact the show doesn't reach a conclusion of any kind.
Sorry to be the bearer of bad news.
Pooch