A GOOD BOOK TO START

Osprey's Basic and Advanced Aviation Modeling. You should be able to find them at any hobby shop.

Paul Boyer put out a good book some years back about building model planes--I don't have the title with me right now, but I'm sure you can get it from him via this website--he's the Q&A columnist for FSM. Aside from that, if you're new to the hobby, I wouldn't worry about detailing or anything advanced yet; build your first few kits "out of the box," then as you gain experience, add only one or two aftermarket or scratchbuilt details to each model, then proceed to add more details for each model you build.

My favorite titles on this subject are unfortunately out of print: "How to Build Model Aircraft" by Roscoe Creed, and "Hints and Tips for Plastic Modeling", Burr Angle, editor. You might be able to find these at a used book store or www. abe.com.
I've actually gleaned a great number of tips from the web, like www. hyperscale.com and www. aircraftresourcecenter.com. The latter actually has a sizeable"tips" section that's really interesting.
Happy modeling!