I have a published book, by a POD, big mistake. Anyone know a publisher, who will republish?

Terminate your contract with the POD - then make some revisions to your book, so it will not be simply a copy of something that is already out there. This is your chance to improve it. Rewrite it. Then find a new title.

Then approach a traditional publisher in the normal fashion. As you have terminated your contract with the POD (and hopefully, you didn't assign the copyright to them) you can approach the traditional publisher with a virtually 'new' book. You probably only sold a dozen or so copies with the POD, so your book will not have flooded the market and won't be widely known or recognized.

Unless your big mistake included transferring the copyright to the POD publisher, or giving them exclusive rights to print your book for a certain amount of time, any other publisher will republish your book. The catch, of course, is that if they're a traditional publisher (the sort who pays the author, not the other way round), they won't want to publish your book unless they're confident it will be a commercial success.

Just tell the POD publisher that you don't want to publish with them any more and ask them to stop offering your book for sale. They shouldn't have any problem with it. Then, when you start querying traditional publishers and literary agents, don't tell them that you published by POD to begin with. It makes you look like a clueless wannabe, and as long as the POD version of the book is no longer on sale, they won't be competing with it, so they don't need to know about it.