Are you looking for the tables for the consumer (the "External tool" module) or the provider ("Shared as LTI tool" enrolment plugin)?
For the consumer it will be the _lti table. But you may have to check _lti_types mdl_lti_tool_proxies if you used the proxy / auto configure to create it.
_enrol_lti_lti2_consumer is the table for the enrol provider.
I'm interested to know why you need access to the tables. Generally everything you need to do should be doable from the interface.
