There’s adclassix – which has several vintage ads – broken down by category – celebrity endorsements, railway, cosmetics, cars, fashion, tobacco, beer and spirits etc.
Ed Murrow advertising coffee
and GBS advertising sleep [Beds/Springs/Mattresses]
There are some decent blog sites as well. Theres Found in Mom's Basement which is probably the best of the lot.
I found a couple at home. They’re from the 70s. This one is truly weird.
The copy goes
“Can you brew bathtub gin?”
“Can you light his fire swiveling to a calypso beat while slugging champagne from a bottle and wearing nothing but one Edwardian rose behind your ear?”
and the truly spectacular
“Do you have to have your carrot juiced every morning?”
and “Be the first on the block with an ocelot”.