When you open up TSM from your Auction House screen, you can look to the right "window" that appears and mouse down till you see the tootip for "Shopping-Milling/DE/Prospecting". Now click.
Now you are going to see this window take it's place. See the little milling icon? Mouse over that, you will see the mini-window to shop for items to mill, then click. Directly below the "s" on items, there is an arrow to drop the menu down......
Materials to Mill (Herbs)
Any Pigments needed for the ink
The ink itself
Now below you will see the exact cost per ink (it starts from the cheapest the AH has). If you have your "browse" tab on Auctioneer open, you will see a quick scan of every available mat, and if you are prone to seizures, I warn you to watch out, as they fly through the options very quickly. Now, you just have to click the "BUY" tab to purchase the goods at the price listed.
*Be extremely careful what you purchase and at what price, as you never know if someone jacked up the price on them.
*Below the information listed (what the item is and purchase price), you will see another small window with a bit of data for you: Total Spent This Session, Inks Bought this Session, and Average Cost Per Ink this Session.
Hope this little bit of info helps you in your Got Mill? needs, and help you rock out more Glyphs to sell in the AH. You might also want to hit up reselling the inks if there is too much competition on your server with glyphs....