It depends on how you are running your import job:
from the command line: last-value is printed on the screen as an output which you can use in next import. Sqoop will not manage it in this case. It's upto the user to keep track of it.
from a saved job: Sqoop uses it's private metastore (in /.sqoop/) or a shared metastore(as specified in sqoop-site.xml) to save job details