As stupid as it sounds, this is a great approach. Of course try to go places where you won't have to see the girl again in case you do get rejected (a highly populated mall would do, or another public place). You really don't want to get rejected by a few girls at work and then have to face them every day for the next ____ years.

And it's pure logic. The more you do something, the less afraid and anxious you are to do it. Ever jump out of an airplane? I have. The first two or three times were scary. After that it got easier and easier till I couldn't wait till my jumpmaster said, "GO!"

Asking girls out is no different. Seriously, all you need is practice with flirting. As your shopping in a store just practice your witty remarks on whoever happens to be near you. Ask random girls how you'd look in a certain shirt or pants. It's fun, and can be funny if you pick the right clothes (like I did once)

Alexi