Added some new places where you can find the BALCHIK book:
9. El Simpatico bar (43.405324, 28.160485)
10. Souvenir Shop opposite New Beach Bar (43.405650, 28.158048)
11. Lotos hotel (43.405759, 28.162452)
11. The Palace of Queen Maria (43.403177, 28.145832)
You are welcome!
Price is 25 BGN everywhere
Figures in brackets denote the geographical coordinates. You can copy them and use in the search at Google maps.