Help with wordlists - cracking md5(unix)

Hi
I'm cracking passwords for the first time and need some advice (all of this is being done for a security module at Uni). First of all, is oclhashcat the best to use for cracking md5(unix) hashes ? From what I have read it seems to be the best one (I have a HD6950). The only issue I'm having at the moment is I can't figure out how to load custom wordlist to be used with oclhashcat, could someone point me in the right direction, would be greatly appreciated.

Thanks !