I found this website [redacted] has huge tsumego collection in SGF format. You may find some of the download links are using linkshrink before redirect to mediafire. (I think the owner wants to get money from linkshrink)
anyway, I paid the membership and get 30,000 tsumego problems. cool!
you can import the SGFs to GoGrinder, ElyGo and Hactar Go.
CHO CHIKUN Encyclopedia Life And Death - Advanced
CHO CHIKUN Encyclopedia Life And Death - Elementary
CHO CHIKUN Encyclopedia Life And Death - Intermediate
CHO CHIKUN Encyclopedia Life And Death - Others
FUJISAWA SHUKO - A Collection of Original Tsumego Masterpiece
GO SEIGEN - SEGOE TESUJI DICTIONARY
GO SEIGEN Evil Moves Tsumego
GO SEIGEN Reading and Training Actual Game Situations
GO SEIGEN Striving Constantly For Self-Improvement
GO SEIGEN Tsumego Collection - The Long-Lived Stone Is Not Old
GO SEIGEN Tsumego Collection 1 - Shokyu
GO SEIGEN Tsumego Collection 2 - Jokyu
GO SEIGEN TSUMEGO DOJO VOL 1
GO SEIGEN TSUMEGO DOJO VOL 2
Hashimoto Utaro 179 Skillful Life and Death
Hashimoto Utaro Famous Creations Three Hundred Selections
Hashimoto Utaro Masterpiece Collection–Moves to Attack and Protect
Hashimoto Utaro Tsumego for the Millions vol.2
Hashimoto Utaro - Nakasendo, Enjoy Tsumego and Get Stronger
Hashimoto Utaro - Fifty Three To Go
Hashimoto Utaro - 1 Year Tsumego
Hashimoto Utaro The Moments of the Wind VOL.1
Hashimoto Utaro The Moments of the Wind VOL.2
Hashimoto Utaro The Moments of the Wind VOL.3
ISHIDA AKIRA Tsumego Masterpiece Collection – Fundamental Tesuji and Repeated Practice
ISHIDA YOSHIO - 3 Dan Tsumego Challenge
Ishigure Ikuro 123 BASIC TSUMEGO
Ishigure Ikuro Go – Sure Kill Tsumegos for Shodan, 2D and 3D
Ishigure Ikuro’s Tsumego Masterpiece Collection
Ishigure Ikuro 6Dan Tsumego Challenge
KADA KATSUJI Tsumego Brilliances Vol 1-4
KADA KATSUJI Tsumego Class
KADA KATSUJI Tsumego Masterpieces Vol 1-8
KAKU KYUSHIN 200 TSUMEGO PROBLEM
KAKU KYUSHIN Increase Your Fighting Strength Ten-fold with Kyushin’s Tsumego
Kano Yoshinori - 239 Graded Go Problems
KOBAYASHI SATORU 105 BASIC TESUJI FOR 1~3 DAN
LEE CHANGHO TESUJI
MAEDA NOBUAKI Delightful Tsumego
MAEDA NOBUAKI Newly Selected Tsumego 100 Problems (Continued) for 1-8k
MAEDA NOBUAKI Newly Selected Tsumego 100 Problems for 1-8k
MAEDA NOBUAKI The God of Tsumego VOL1
MAEDA NOBUAKI The God of Tsumego VOL2
MAEDA TSUMEGO - Tsumego for the Millions 100 VOL 1
MAEDA Nobuaki Tsumego Masterpieces
MAEDA TSUMEGO Collection - CHUKYU
MAEDA TSUMEGO Collection - JOKYU
MAEDA TSUMEGO Collection - SHOKYU
MAKING SHAPE TESUJI
SAKATA EIO TESUJI
SATO SUNAO - FLEXIBLE TSUMEGO
SATO SUNAO - REFRESHING TSUMEGO
TESUJI GREAT DICTIONARY
TSUMEGO CLASSIC - GENRAN
TSUMEGO CLASSIC - GOKYO SEIMYO
TSUMEGO CLASSIC - GOKYO SHUMYO
TSUMEGO CLASSIC - GUANZI PU
TSUMEGO CLASSIC - XUAN XUAN QI JING
WEIQI LIFE AND DEATH 1000 PROBLEMS
YAMADA KIMIO Interesting Tsumego Dojo
YAMADA KIMIO TSUMEGO BOOK1 - BASIC TSUMEGO
YAMADA KIMIO TSUMEGO BOOK2 - HIGH SPEED ATTACK TSUMEGO
YAMADA KIMIO TSUMEGO BOOK3 - ROAD TO 3 DAN
RICHARD BOZULICH - 101 BASIC STRATEGY
GET STRONG AT THE OPENING
GET STRONG AT HANDICAP GO
GET STRONG AT ATTACKING
GET STRONG AT INVADING