offset-list is not used with ISIS.
Distribute-list can be used to leak routes from L2 to L1 or filter when advertising L1 into L2. See examples:
http://www.cisco.com/en/US/customer/tech/tk365/tk381/technologies_tech_note09186a0080093f39.shtml
Hope this helps,
Harold Ritter
Sr Technical Leader
CCIE 4168 (R&S, SP)
harold@cisco.com
México móvil: +52 1 55 8312 4915
Cisco México
Paseo de la Reforma 222
Piso 19
Cuauhtémoc, Juárez
Ciudad de México, 06600
México