Gold Tone is located in Titusville, Florida and was founded by Wayne and Robyn Rogers in 1993. They are a US company who do a little manufacturing, (of Banjos), and a fair amount of assembly in the US but I believe a lot of the components are manufactured in the Far East. When you look at some of the model though, I would say they are completely made in the Far East and just rebranded by Gold Tone. 

They started out with, and are predominantly know for Banjos, but over the years the catalogue has expanded to include Banjoleles, from Soprano to Baritone scale, and most other common chordophones, (not standard Guitars though), even a couple of Soprano Ukuleles based upon Martin designs. They also have their branded version of the Resonator Ukulele that comes as a standard Concert or a Tenor scale Superconcert.

In 2012 they introduced an less expensive range of Banjos and other chordophones they brand as GT. Included under this branding is a 23 inch scale Ukulele Bass based on Aquilas ShortBass One, they call the MicroBass. I have also seen, though it is no longer in their catalogue, a GT branded "Smile" Ukulele, it differed from most by being Concert scale, (and five times the price). 

In 2017 they dropped this branding and brought everything back into the Gold Tone fold. they extended the Uke Bass range to include a 25" scale model and solid body Uke Bases. In 2017 they did some kind of consultant/licencing deal with Paul Beard for their top end resonator Guitars, so far this deal hasn't included Ukuleles though. They have also launched two new brands, Wood Song for acoustic Guitars and Earth Tone for Drums; no Ukuleles in these ranges either.