Not on purpose!
After my tank cycled, I added astrea and trochus snails. After a couple months, I noticed one of the trochus one night, perched on a rock right in front of a powerhead. It wasn't a "normal" place for a snail, so it caught my eye. Just as I moved in closer to look, it released a smokey/cloudy stream from under it's shell. It did this 5 or 6 times. I figured it was "casting its seed" so to say, but didn't think much more of it.
Fast forward a couple months later, and I start to see some really tiny baby trochus snails scooting around. Fast forward a couple more months later, and I now have about a dozen small 1/4" inch diameter trochus snails, and a couple 1/2" diameter trochus snails. Go figure. They're awesome though... they're getting into spots on my rock that have never been touched!
I've also spotted a couple baby astreas... maybe 1/4" in diameter, but never saw that dirty deed.
Someone here mentioned on a different post that conditions aren't right in home aquariums to reproduce and that any baby snails we see are just hitchikers from the original live rock. I don't buy it in my case. It's just too coincidental that shortly after I see a spawning event, baby snails of the same type show up. And the baby snails I'm seeing just happen to be the two exact kind I put in my tank to start with.
If you're looking for specific info, I probably can't help you much. Here's my water parameters for what it's worth...
Lighting Schedule (196W on a 46gallon)
Actinics - 9:30am until 9:00pm
10k - 10:00am until 8:00pm
moonlights - 9:00pm until 8:00am
...and I don't have anything that'll munch little snails. Only a O. Clown and a Bangaii Cardinal.