How to get my passport back to me in Michigan from a travel agent in California, when he wants me to buy his services?

I assume here that you did not sign any contract with this agent, since you do not mention that. If you did, please update your question as this would be a very different matter.

You have several options, but before pursuing any of them you need to reach out to the agent in writing and politely ask for your passport for being returned by overnight/priority mail at your expense. You can prepay the priority mail envelope at usps.com and send it to him by mail, or - even better - send an envelope with prepaid label to him inside another envelope.

Then get his reply whether he will or will not do that. Again, you need all this in writing. You can add optional threats to complain/sue if you want.

The reason for this is that you need evidence to prove that he actually possesses your passport in the first place. It is unclear whether you have any such evidence at that moment, and without it he may answer to Court/FBI/whoever that he doesn't know what you're talking about, as he never seen your passport.

Then you have several options, depending on how much the requested amount was - and assuming the requested amount was unreasonable - and how much you are pissed off:

1. Haggle; ask why the amount is so high. $50 for mailing it back next morning via overnight mail is reasonable, but $2000 is not. There may be an explanation for that, and you might be able to negotiate if you want to.

2. Send him the requested amount of money, receive your passport, and file the police/FBI complain for extortion. Check with a lawyer before writing your mail if you are going to do this, as some specific wording might be required in your state. This will likely only trigger any attention if the requested amount was large enough; I doubt FBI would care about $100 extorted.

3. Sue him in a court (after you send him the requested amount of money, and received your passport, or before). Check with a lawyer before writing your mail if you are going to do this (you don't need to retain this lawyer to represent you). There are several options here, and you can do this together with option 2:

   (a). If you want to visit California, you can sue him in a small claims court there. You can ask the Court to award you the reasonable (no private jet) travel expenses. You'll likely have to go there at least twice. You must sue in his county (there are other restrictions as well).

   (b). You can hire an attorney in California, and sue him in a state court there;

   (c). You can hire a local attorney, and sue him in a Federal court in Michigan.

   Keep in mind, that you might win a judgment but this doesn't mean you'd get paid. Especially if this agent is of a dodgy type. This is yet another reason why you need an attorney, who can better assess your chance of recovering anything.

4. As Zach Lipton suggested, you can try to get a new passport instead. I would not recommend this option, since you'd have to claim your passport as "lost or stolen". Those reports are counted (and your new passport will have a print "this passport is issued as replacement for a lost or stolen passport"), and if you manage to lose another one, you will only get a limited validity passport instead (scroll down to the bottom). Thus it is the least desirable option.

5. Finally, you can send him the requested amount of money, receive your passport, and do nothing else (maybe write a bad Yelp review for him). Just write this off as shitty experience, and forget about this. If he asked for something like $100, this would probably be the most reasonable option.

I would tell him he has 24 hours to mail it back or the police will be called. If he doesn't overnight it, call the police and report it stolen.