Hi SB, as far as the table saw goes, I've had good luck using 3in1 oil and a fine steel wool (00-0000) to remove rust from some tools I inherited. As for the corded power tools, the only thing I can think of is to disassemble them and clean as needed. I don't belive WD-40 will inhibit rust (to my knowledge), but there is some product on the market that's suspossed to, but for I can't recall what it is (sorry). Maybe a search of the internet on rust and inhibitor would result in a good find.
And as the regular moderator would say... my best to you, and I hope this helps! Wick!