Sat Nam! (Literally "Truth Name"--a Sikh greeting)
There's the book that's my avatar, Sikh Spirtual Practice, an excellent guide to what we do.
You can also check out
www.sikhnet.com
The language is a bit antiquated and lengthy in 3 vols, but Max Arthur Macaulife's The Sikh Religion is an excellent guide to early Sikh history.
There aren't too many books about Sikhs just as people, though my book does have some of that. You might try The Sikhs (I'm forgetting the author), but I haven't read it and am not sure how good it is, though I've heard it's got great pics.
Unfortunately, most translations of Sikh scriptures are written in "Hinglish," but The Wisdom of Sikhism published by Oneworld is excellent, though just a sampling. And Macaulife included lots of translations (again, somewhat archaic) in his text. I've got some too (more contemporary language).
Hope that helps.
Blessings,
Siri Kirpal