When moving to gmail from ihug using thunderbird, will my local folders still be available that were set up under ihug?
In general yes, as long as the ihug account was set up as POP3 then the messages retrieved from the server and permanently stored on your hard drive (until you delete them off it yourself).
If the messages are important it might be a good time to create a backup of them anyway.
Thank you. That was what I needed.