Liz, hosta doesn't grow from bulbs, they have roots - lots of them and they are long. One of the few times I've broken a shovel while gardening was attempting to dig and divide hosta. Our zones are quite different, but I suspect it's too late to transplant with complete safety in your colder climate.

Here is a link that might be useful:

Hostas are very hardy, so you needn't worry about the cold. You can dig, divide (if needed), and transplant now or in early spring. Don't tarry if you are to do it yet this year.

Al