B&N’s Nook will finally launch in the UK (but who’s going to sell it?)

Barnes & Noble (s BKS) is finally launching its Nook e-readers in the United Kingdom. Starting this October, the Nook Touch and Nook Touch with Glow Light will be available through nook.co.uk. (No Nook Tablets or Nook Color for now.)

In addition, the company promises that the e-readers “will also be available through partnerships with leading retailers” with “established physical and online channels” and those partnerships are expected to be announced “shortly.” Details on availability and pricing will also be announced “in coming weeks.”

However, it is unclear who those partners will be. Barnes & Noble and leading UK bookstore chain Waterstones were widely expected to announce a Nook partnership earlier this year. Instead, to the surprise of many, Waterstones partnered with Amazon (s AMZN) to sell the Kindle in its 300 stores. (Amazon launched its UK Kindle store in August 2010.) Smaller e-reader player Kobo partnered with bookstore chain WH Smith last October. Assuming that WH Smith won’t sell e-readers from another brand, that leaves general retail or electronics chains like Tesco, Asda, Currys PC World and John Lewis as possible partners for Barnes & Noble.

Microsoft (s MSFT) invested $300 million to spin off B&N’s Nook and college businesses this past April, and will spend $25 million a year for the first five years to help cover the costs of the new company’s international expansion. Barnes & Noble has around 25 percent of the e-reader market in the United States, compared to Amazon’s estimated 55 to 60 percent.

Barnes & Noble will announce its Q1 2013 earnings Tuesday morning.