To get an items ID, you need to go into your inventory, the item market, auctionhouse or a shop and find the item whose id you want. Then click on the corresponding [info] link.
Then look at the URL, and its ID is the number at the end:
In this case, the xbox 360′s id number is 145. Now to get the auctionhouse to show only xbox 360′s, i would type into the address bar: https://www.torncity.com/amarket.php?iname=145
Note: We now have a list of all item ID’s on this page under items: Item Checklist/ IDs