Authors' series

[observer3]

I have been reading beesandbrews Torchwood series and thoroughly loving alternate looks at the world of TW through other authors' eyes.  Are there any other similar collections of stories that pre-date the series, occur during season 1, 2 and 3 and in between the seasons.  Not really interested in season 4-unless the original team is involved.  New character who are new team members are of an interest.
many thanks for all suggestions in advance