actually you can. TSM is an addon that searches most recent auctions on the AH and gives a list to you of the ones you may be interested in based on your set parameters. TSM lets you bind buy auction to mouse over scroll wheel. all it takes it hover over the item and scroll. it is that fast manually.
people dont want to believe it, but AH bots dont really exist. there is just too much room for error when it comes to sniping. you need to know items value and if something is worth buying.