Yeah, 90% of your audio proggies will do it for you, some allow you to adjust the spacing while previewing.
I do it manually not because I walked up hill both ways in the snow as a child (I did, but thats a different story), but because for a long time in Audacity on the mac, the VST plugins didn't work properly and I was too cheap to pay for a real program and couldn't find one as an AU format.
Now there are some, and I just don't care.