Question How do I come up with names without using ones that have already been used or sound like real people? Answer:
I take it you're writing fantasy and want names that originate in a made-up culture? Most names in the real world are constantly being reused and duplicated.
One approach is to consider what sounds you want your culture's language to be based on. For instance, Italian sounds very different from Gallic or Japanese. You can take the flavour of a given culture - the sounds, rhythms, etc. of the language - and apply to them to your fantasy culture. You can take traditional names from a given culture replace certain consonants or vowels, or alter the spelling a little, to create original names.
Alternatively, you might look at names that were common in ancient cultures that few people would recognize today.
Of course, the other option is to just make them up.