To get to the tent, head north along the bridge and head east southeast, it's hard to miss.
The GETEOSSETEVENT code is for free lowbie armor, and the LT01LUCKYPORTA code is for a cash voucher that appears in your chest which sells for 10k-30k
Choose the option which related to your code, walk up to the lady, choose the first option, and type in the stamp code.
IF YOU FAIL TO ENTER A CORRECT CODE 5 TIMES YOU WILL HAVE TO WAIT FOR SOME GOD AWFUL LONG AMOUNT OF TIME BEFORE YOU CAN TRY AGAIN.
You'll know you got it correct as it will place some gookrunes stamp in the white box below where you entered the code.