Through ALL of Orange County, and near the coastal areas, Laguna Woods would probably be your very BEST bet. Although, even there it is quite hard to find a one-bedroom condo, and again, it's an active adult community.
Now, by just altering your search parameters from $100k, to closer to $200k, you really open up so many more options. For instance, there is a pre-foreclosure in Dana Point at that price, as well as a few condos in Laguna Niguel, and yes, even a one possibility in Huntington Beach.
So, while it's not the easiest thing to find, because these great little values don't come up every day ~ hopefully that gives you a bit of hope that there would be some possibilities for you here!
If you would like to search the MLS go to my site
First Team Real Estate