You can prevent being shilled by :
Bid once bid late and bid only your maximum.
OR
Bid once, bid only your maximum, and use a sniping service that will place your bid at the very last nano-second.
These both have the same effect, obviously.
Remember, shills don't want to win. They want YOU to win, at your highest bid.
And they bid to push you up, until they beat your max and then they retract.
Late bidding avoids that.