oh please, what difficulties in cultivating nightcrawlers might possibly be, the only downside if long maturing process, other then that it is same as earthworms. easily done even at home, if one can ensure proper temps.
bcreps - you can always ask, but if i were you I'd just go and get from fishing supply stores

do you really need to get 500+ worms? and to ship just a few cups it is gonna be very expensive, they offer free shipping to US, but charge tons to ship to Canada.
in stores they are also called dew worms. everybody with frogs are getting from fish bait supply stores and nobody had ever any problems

the only reason i ordered from internet was because i needed big amounts.