I'm going to be wiring an addition to our house and would like suggestions on drill bits and electric or air right angle drills. Part of the addition will involve drilling through double 2x10 joists, some with somewhat tight spacing.

Thanks,
Bob

Milwaukee Right-Angle with a 3 foot extension, I dont like the Hole-Hawg too heavy.
As far as bits are concerned the Milwaukee self-feeds cant be beat.
The down-side if there is one, out the door, is about $400.00

Wm.colt

Look at cordless "impact drivers." Fine Homebuilding did a review not so long ago. These tools will power a drill through heavy wood, without grabbing and breaking your arm.
The Milwaukee rep demonstrated his- no problem dending a 3" "forstener" through a 6x6! And Milwaukee fared poorest in the FH review.