Most of us have had excellent results with the Elechouse PN532 V3 unit which you can set to connect to an arduino via I2C. This is what I've done in my car starter, and what was done with the desktop logon unit I linked to earlier. These can be ordered from Elechouse, I wouldn't recommend ebay or any other site as there do seem to be a lot of clones out there that look the same but don't function near as well. Depending on your programming knowledge or how much patience you have you can set up your arduino sketch to deal with UID only, stored data, or both.