I have a 2000 SSEI, which I totally love! My issue is this: my trunk has started to leak. When I have called numerous part stores, they have told me they don't make a seal of any sort for the spoiler. My son tells me different. Is this a part I have to get from the dealer?

There are rubber washers to fit the Spoiler hold down bolts. (Dealer item) Also check the trunk gasket and make sure it hasnt become unseated or have a hole/split in it. Trunk leakage is a common problem for Bonneville'*. Even the 05'*

yes check the spoiler, the taillight, and the third brake light