The code is located by the coffin in Twilight Fields, the code is 0451. Inside ther is a EVE Hypo, Automatic Hack Tool, 00 Buck and Standard Auto Rounds. (Can't be hacked)

The code is found on the Audio Dialogue " Picked Up Timmy", the code is 5380. Inside there is a first aid kit and ammunation. (It can be hacked / bought for $58)

The code is located on the Audio Dialogue ""Masha Come Home", the code is 7533. Inside there is Money, access to the Shorten Alarms Gene Tonic after listening to the audio diary Saw Masha Today. (It can be hacked / bought for $58)

This code is located on the window marked by scribblings, the code is 9457. The door must be opened in order to progress. (Can't be hacked)

The code is located on the Audio Dialogue " Market Maintenance Code", the code is 0512. Inside there is Money, First Aid Kit, invention components and ammunition. (It can be hacked / bought for $251

The code is on a note on the floor, the code is 7774. Inside there is Money and Electric Buck or antipersonnel Pistol Rounds. (It can be hacked / bought for $251)

The code is found on the Audio Dialogue "Kyburz Door Code" as well as various calendars and posters with Australia Day marked, the code is 0126. Inside there is a quest item, access to a Power to the People station, invention components and ammunition. (It can be hacked / bought for $251)

The code is on the Audio Dialogue "Fontaine's Breakup", the code is 5744. You must open in order to progress. (Can't be hacked)

The code is located on the Audio Dialogue "Extra Munitions", the code is 1921. Inside there is 3 EVE Hypos, invention components and rare ammunition. (It can be hacked)

The code is on the advertisement for Zimmerman Chardonnay, the code is 1951. You must enter in order to turn on the Ferris wheel.

All of the credit goes to http://bioshock.wikia.com/wiki/Codes since all of the information came straight from there! Hope this helps!