Whats the one thing I should know?

Best pates (meat or fish pastry turnovers) are at Ashley's near the entrance to the airport parking lot.
Good, cheap breakfasts & lunches - Delly Deck at Havensight or Hook, Line & Sinker on the water at Frenchtown.
For liquor, probably K-Mart of Cost-u-Less.
Shipwreck across from Havensight to meet people, or Betsy's in Frenchtown or Duffy's in Red Hook & don't forget the Sunday beach party at Sapphire Beach.

Bring Cash, all you can :). Drivers License, Birth Certificate (with raised seal), social security card original unlaminated in good condition, passport (no you don't have to have it technically but it makes life easier). As for food and booze Trade gave good recommendations for that but make sure you bring cash :), did I already mention that? Also when you get here and need to get on line and you find out it may take weeks depending on were you are staying, we found a good hot spot and a good lunch at Captain Mayhem's in Havensight across the street from the cruise ship dock right beside the Tram.
Good luck and welcome,
Jay

Why so much cash Jay? I don't remember needing much and we do have atms and banks. Do bring your SS you will need that not a joke. Are you coming to stt or stx or stj?

If you are going to rent an apartment then you will likely need first last and security. Which means a minimum of $3000 to get into a decent apartment and very likely more than that. We chose to buy a car and pay for it as apposed to having a car payment. Which obviously meant settling initially for allot less car than we were used to in the states and only one car for now. Also the initial trip to cost us less to stock up was well over $500.00. We also have run into more than one establishment that takes only cash. I won't go into the no paper trail not taxes theory behind this. The cash isn't 100% necessary but it is easier. You can open an account here and deposit a check from your stateside account but it may take up to two weeks for it to clear. The other option is to wire money from your stateside account but it will take time planning and money for fees. So yes Betty there are options to cash but cash is easier. I also put my smileys behind it for tongue in check because I am having a great time in my new home but if you come hear thinking the rumors about it being expensive aren't true you are going to be sadly mistaken.
Jay