For mounting on the wall, I would use brackets they use for normal shelving (L bracket with a brace) but instead of the bullcrap achors that come with them, anchor to the wall using toggle bolts, unless you hit a stud, then just use a small lag bolt.

then on the top put a couple L brackets on, to help keep the rack sitting on your bottom brackets, opposed to the rack wanting to tip forward off the brackets. unless your bottom brackets are big enough to prevent this from happening.