For the wood I went to Lowes and had them cut a 2"x12"x12' piece of white pine in half. White pine is soft enough to beat up but will support your items. And if the guy at the saw tries to talk you out of your lumber selection because all the knots in it, you know you chose a good one!
You need to make sure the width is enough to fit whatever you're placing on the shelf. My shelf is for 10" dinner plates. If you weren't already aware, a 2x12 is just the name. The actual measurement is closer to 1.5x11.5. So to be safe I got the 12" width so my plates wouldn't be teetering on the edge of the shelf. I have them cut my lumber down at Lowes because 1) I wanted to be able to easily get it into my car and 2) taking pics of my lumber in front of the big saw is my m.o.
I wasn't needing my wood shelves to be 6' long, so I measured and chopped them down a little more when I got home. But you could have the store cut your wood to your exact dimensions if you didn't have a saw and knew what exact dimensions you needed. Not saying I didn't know before hand...but not saying I did. When you get your lumber home, beat the snot out of it. Below is the highlight reel of my method. You can really use anything metal you want: hammer, nails of different gauges, chain, screws, etc.
One of my favorite effects I did was banging the edges on all sides (top and bottom) with the hammer. It makes it look more like rough cut milled wood. Then stain your little heart out. On my first pass I thought the stain I had on hand was way too red. So I watered down some black acrylic craft pain and mixed that. Stain, wipe, paint, sand, repeat until you have the desired color. I'm not even going to give the stain color I have because it seriously is super red and only looks semi-decent with the black wash on top. The great thing about the black paint though is it sinks into the distressing and pops with that horrifically red stain. If you're DYING to know though what stain I used, you can email me and ask me nicely in a big run on sentence so I feel right at home. Extra points for sarcasm!
After you've reached max level of wooden awesomeness, seal your wood with polycrilic. I use Minwax Polycrylic (blue can) for everything and LOVE it. Fully endorse that product (even though I've never been asked to!) I always have it on hand because it doesn't yellow white painted furniture. So I use this on everything.
The shelving part was easy and mildly therapeutic with all the beatin' and distressing' going on. The hardware took a little more brain power. One glance down the plumbing section for metal elbows, flanges, and pipes, I knew this could quickly become a COSTLY project. (Read: non exsistent). Ebay to the rescue folks. I found a great tutorial here and contacted the ebay shop she had used. Super nice guy with great communication. Instead of purchasing each piece separately, I sent him a list of what I needed and he sent me a price quote the following day. I had all my supplies within a week.
To make two shelves (with two support brackets each) I needed:
 ¾" flanges
 ¾" elbow brackets
 ¾" x 2" pipe nipple
 ¾" x 5" pipe nipple
The type of metal used was black malleable. My total was $47 with $4.95 s&h. Had I purchased this at the store it would've been well over as the flanges alone totaled roughly $48 in store.
I went over them with a light coat of hammered metal spray paint. Mostly to cover the printing on the pipes and seal in any dirt. Makes complete sense right? Assemble like so
I actually secured a flange to the wall (using a tile bit to pre drill through the tile) before screwing on the 5" pipe. Make sure you're completely level when you attach the two brackets.
Screw the opposite flange up into the wood. To be more accurate I laid the wood on the brackets, marked each hole with a marker and pre drilled a pilot hole into the wood. This made attaching the brackets to the wood a breeze. Then step back and bask in the glory. To be 100% honest, after putting all my beloved dishes on the shelves, I ran out to check my shelves the next morning to make sure nothing came crashing down during the night.
I'm happy to report these have been up for a couple months and have been loaded and unloaded with dishes several million times. Still going strong. Still make me smile every time I walk into my kitchen. I have to put a small piece of trim at the top of the tile...so don't look too closely at the photo.
You just looked, didn't you?