It works great and one of my favorite strategies. 

@Scott Ray my personal favorite is the cash out refinance.

You can try keyword searches on Zillow/Redfin/pick your favorite site, but it might be harder to find.

Yep, sell off some of your least favorite long term rentals but make them real nice first so owner-occs will want them.  

I bet someone out there is doing it...Let's say $4.50-6 (low end quotes on smaller singlewide) per mile on top of the typical hookup & setup etc costs.1000miles $4500-6000 extra (vs local  <100 mile move)1500miles $6750-9000 extra2000miles $9000-12000 extraAdd ~ $1000 to that to be safe..for any additional inspection, trip permit, tires, trucker hotel room, etc costs.Based on the seemingly inflated prices of used mobile homes here I do think there may be areas of the country where prices on average might be $5500-13000 less than what I see in my area.

Figuring out the nuances of financing these deals is the hurdle that's tripping me up.  

Any of your favorite books on the subject.

This all being said, my least favorite answer to here to those questions is, "Well if it is a good deal and the numbers work, I like it." 

What are folks favorite websites to get best practices and insider tricks on how to do this?

Tenants (and buyers) favor it.