My advice (given as an atheist, mind you) is to start picking up the many time-limited promotional free books the Christian publishers give away in most of the stores practically every week.
From there, sample them at your leisure and try to figure out if there's a particular author or theme that you like. Apparently the Amish subgenre of CF is very popular, and there seem to be a lot of spooky suspense thrillers offered every so often.
Here's the promotional free books page over at the
Christian Books e-store. Unfortunately, they seem to be affiliated with that rather unpleasant
Focus on the Family organization which advocates spreading lies and enforcing bigotry by curtailing the legal rights of non-believers, and openly solicit donations for them.
But I suppose everyone has their flaws and otherwise their store seems a good place to see many of the current freebies gathered into one area (although they're missing some and you should check the Deals forum here for new ones) and browse for purely Christian books that are guaranteed to fit suitably into what you've previously mentioned about your reading material preferences.
Hope this helps. Oh, and as a personal recommendation, I tried and liked Amy Clipston's
A Gift of Grace (seems to get offered free every once in a while), which I felt was a pleasantly non-preachy, non-judgmental and genuinely faithful story which also came with some nice-looking Amish recipes. This may or may not be to your taste.