The Region 2 release is slated for August/September. On one of the Without a Trace discussion lists I frequent, one of the production people posted that work is underway to put the first season on DVD. I always take posts like that with a grain of salt, because anyone can claim they're something they're not. But the Region 2 release has been advertised (at least on Play.com), so I suspect a Region 1 release can't be too far behind. Brukheimer's CSI first season was released in the UK a good year before it was released in the US, but now, season 3 was released in the US months in advance of the UK. So I wouldn't be surprised to hear an official announcement in the next month or two that DVDs are scheduled.
It would be good for them to capitalize on the show's growing popularity and LaPaglia's Golden Globe win. If they can follow up with some Emmy wins, the powers that be would be nuts not to take advantage and roll the show out on disc.