I've compiled a short list of book clubs in SL: https://docs.google.com/document/d/1YWw07Va0y7zVWuQIWaxQtGSDOwqR3-eSrkT_t0Vi474/edit?tab=t.0
As someone else mentioned, the TNC book club is highly recommended!
Silent Book Club in Second Life has several meet ups. Readers gather to share about the books they're reading, then spend an hour together reading their RL books. It's a nice way to meet fellow book lovers...and could lead to organizing your own book discussion group.
Here's the current schedule for Silent Book Club in Second Life:
1st MON, 5PM SLT - 13th Moon Books
Location: 13th Moon Books http://maps.secondlife.com/secondlife/Woodland Hills/44/223/22
Host: Maia (maia.morningstar)
1st WED, 3PM SLT - Unbridled Books & Coffee Shop
Location: Evergarden http://maps.secondlife.com/secondlife/Crystal Shores/195/27/33
Host: Witchie (elaine.evergarden)
3rd FRI, 10AM SLT - Bay City Public Library
Location: Bay City http://maps.secondlife.com/secondlife/Bay City - Imaginario/208/115/28
Host: Stable Mum (friendly.fairelander)
4th THURS, 2PM SLT - Sonder Books
Location: Cerulean Sea http://maps.secondlife.com/secondlife/Cerulean Sea/46/126/30
Host: Emm (emm.evergarden)
4th FRI, 7AM SLT - VWEC Info Center
Location: VWEC Eduverse Info Center http://maps.secondlife.com/secondlife/VWEC Eduverse/209/153/30
Host: Malia Rose (blumomo)
4th SUN, 6PM SLT - The Reading Room
Location: Seogyeoshire http://maps.secondlife.com/secondlife/Gundeulbawe/41/164/44
Host: Zoe Foodiboo