Adding an IV to an AES implementation I have an embedded project that requires AES, I seem to have found an AES implementation that fits the bill here: http://www.literatecode.com/aes256, but it does not include an IV. 

Are there any documents detailing the standard way to implement an IV? I looked up the FIPS 197 spec and there is no mention of an IV.
AES is  a block cipher which actually only "maps" (encrypt) a 128 bit block (plainblock) to a 128 bit block (cipherblock) and vice versa. This "mapping" is key dependent.

To encrypt some data you normally apply an encryption mode like CBC, CTR, GCM etc. using e.g. AES as block cipher within this mode. These modes normally require an IV or Nonce.

So, not the actually AES requires an IV but the mode used to actually en-/decrypt data.