Here is another website which has a great Collection of all Gurbani Katha CDs by Giani Sant Singh Ji Maskeen . Some of the very popular Kathas by him as
seen on Tv can be found here . Following are the titles present there :

MP3s
1. Gyan Da Sagar
2. Sangat Da Phal
Reference:: Sikh Philosophy Network http://www.sikhphilosophy.net/maskeen/14624-giani-sant-singh-ji-maskeen-website.html
3. Mool Mantar
4. Man Mandar
5. Nanak Leen Bhayo Gobind Sio Jio Pani Sang Pani
6. Brahm da Gyan
7. Nitnem
8. Sikhi Da Sampooran Saroop - Sikh Singh Khalsa Vol1 -2-3-4-5
VCDs
9. Sikhi Da Sampooran Saroop - Sikh Singh Khalsa Vol1
10 . Sikhi Da Sampooran Saroop - Sikh Singh Khalsa Vol2
11. Sikhi Da Sampooran Saroop - Sikh Singh Khalsa Vol3
12. Sikhi Da Sampooran Saroop - Sikh Singh Khalsa Vol4
13. Sikhi Da Sampooran Saroop - Sikh Singh Khalsa Vol5
14 . Sikhi Da Sampooran Saroop - 5 Vol set of 5 VCDs
15. Guru Manyo Granth
16. Aadyatmak Sarrot
17. Nanak Moorakh Ek Tu Avar Bhala Sansar
18. Jug Chaare Dhan Je Bhaavai (Sachkhand Harmandir Sahib To Aae Hukamnamian Di Katha )
19. Prakash Diharha Guru Tegh Bahadur Ji
20. Shardhanjali Samagam - Baba Bolte Te Kaha Gaye
21. Gurbani Vichar
Audio CDs :
22. Saadho Ki Dhoora
23. Japji Sahib - Rehraas - Kirtan Sohila - Ardaas
24. Is Dehi Ko Simreh Dev
25. Jan Nanak Eah Khel Kathan Hai
Reference:: Sikh Philosophy Network http://www.sikhphilosophy.net/showthread.php?t=14624
26. Man Sthiti - Par Sthiti
27. Hai Hazoor Kat Door Batao
28. Jaap Sahib - Sawaiye - Chaupaee - Anand Sahib
29. Jaap Sahib - Sawaiye - Chaupaee - Anand Sahib
30. Aad Purakh Kartar Karankaaran Sabh Aape
31. Chaar Yug
32. Kita Pasao Eko Kawao Tis Te Hoye Lakh Dariyao
33. Aawan Jaan Ik Khel Banaya Aaagyakari Kini Maya
34. Brahm Bichar Bichare Koi
35. Sukhmani Sahib
36. Puran Jot Jagae Ghat Mein
37. Aawan Jaan Ik Khel Banaya
All these CDs of Wonderful , Knowledgeful , Soul pleasing Gurbani Kathas of
Giani Sant Singh Ji Maskeen are available at JSKS Gurbani Multimedia - All Kinds of Gurbani Kirtan and Katha Cds , Gurbani DVD's , Gurbani Mp3s - Gurbani VCDs - Sikh Cds