Don't know about two tone mats and trunk liner but Weathertech and Husky Liners both offer products for the Gen1 Volt.
A 12V jump starter is a good thing to carry in your Volt, especially on trips. You don't need a high capacity jump starter. One with 6000 - 8000 mAh should be fine (the Volt does not have a 12V starter motor, you only need enough power to boot up a the Volt's computer.) Check on Amazon; occasionally Woot will run a daily deal on these jump starter packs.
A 12V jump starter is a good thing to carry in your Volt, especially on trips. You don't need a high capacity jump starter. One with 6000 - 8000 mAh should be fine (the Volt does not have a 12V starter motor, you only need enough power to boot up a the Volt's computer.) Check on Amazon; occasionally Woot will run a daily deal on these jump starter packs.