1941 bottle of port
That's...kind of specific. I'd recommend the phone book for this one, as well as wine searcher. I've never bought/tasted alcohol more than a year or two older than me and I cannot recall seeing port that old outside of portugal. Something of that caliber would need special storage, if a "1941" even exists. Try Total, Leon's, Vintage Liquors and anyone else that is a step above a Pepito's liquor store.
I would call Wine Watch in Ft. Lauderdale, www.winewatch.com (nothing is listed for 1941 on their website, but call them) they may not have what you want in stock, but may be able to help locate it for you. Additionally they have access to many collectors that may be sitting on something that's for sale...
For port it's going to be very hard to find, as only one major port house (Quinta de Noval) declared 1941 a vintage year. Vinatage port is only made in years the houses feel are best for the conditions to make ideal port. They can sometimes have huge gaps in years.
But if you want a dessert type option, then sauternes or cognac/armagnac are going to be your best bets for 1941, but pricey ($400-2000) and very rare to find but easier to locate then 1941 port that isn't a colheita (tawny port).
If you're in Fort Lauderdale my inclination would be to give Roberto at the International Market (17th Street) a call. Not so much for what he may have in stock but for who he knows and his suppliers.
Roberto loves wine and is close to the importers/distributors. He's pretty much always there. If Carla is tending shop, give her your number and it will get passed on to Roberto.