There have been a couple posts in here regarding wind compensation. Basically, the idea is to calculate approach vectors given the speed of your aircraft, speed of the wind, and angle between the two.
Quick, no-math figuring of the course adjustment to compensate for the wind.
First step: Figure the angle between your course and the wind. For example, if you were flying a course of 135, the angle would be 45° from astern. Then look up the wind angle and the wind speed on the chart below:
The number
above the diagonal slash is the crosswind component; the number
below the slash is the direct component. If the wind is behind you,
add the direct component to your TAS (true airspeed); if it is in front of you,
subtract the direct component.
Second step: Look up the course correction on the chart below, using your adjusted TAS and the crosswind component. The number is the number of degrees you need to turn into the wind to cancel the sideways drift from the wind.

If you have correctly compensated fro the wind drift in your course, not only will you fly a 'straight' course over the ground, but it will eliminate any sideways drift in your bombsight that you have to calibrate for. Of course, if you turn to line up on your target, all this goes out the window, and you have to do it the hard way in the sight calibration, so you might as well learn to do drift compensation in sight calibration.