DVDPlanet still has the DVD version for $60 and change, along with Peacekeeper Wars for ~$10.
Amazon and Best Buy both have the Blu-Ray version for $69.99, and they both have Peacekeeper Wars on DVD for ~$8. All of the above are Brand New BTW.
If you guys want to get the better quality, look to the Blu-Ray set. The video's slightly better (but not much) with the Blu-Rays than the DVDs, but the audio quality is several times better. The Extras are similar, if not a little extra added to the Blu-Ray, between both...Peacekeeper Wars is not available in Blu-Ray anywhere right now (with the exception of the European Blu-Ray release, which is extremely hard to find).
With the announcement of a Farscape movie in the works as of late on the interwebs, now is the time to convince yourself to collect this one of a kind series. This is one of my all time favorites among sci-fi.