I have had similar thoughts recently as you. My idea is to create a DVD to hand out at gurdwaras which can contain katha in english, nitnem, and literature, Each dvd can hold about 4.7gb. and 100 dvds on amazon costs about £20. After searching on the internet, i found two good websites where there are a lot of excellent PDF ebooks on sihkism
http://www.sikhroots.com/docman/cat_view/67-resources
http://www.rajkaregakhalsa.net/literature.htm
There are perhaps a few dodgy ones on the 2nd website from sikh missionary society. However there a lot of excellent distributable resources on both websites. Here is another link which i found during my search which may be of value. Ive been able to put about 40 of the PDF books onto my kindle with no problem, they can be directly converted to kindle format.
hope these help.