I thought that it might be helpful to have a current list somewhere, so I put one together, grouped generally by type of construction. I've included links where I could find them.
Within each group, they're in alphabetical order. If you want prices, many of the makers include them on their websites, or include contact info to inquire about pricing. For the few makers who only sell wholesale, prices can be found by doing a web search for the brand name to get dealers' prices.
For sound samples of a number of these makers' instruments, check out this thread. For more information (around a paragraph each) about many of them, see the Makers and Repairers page of Chris Timson's Concertina FAQ.
If I missed any (or if there are any errors here) let me know! It's great to see how many makers are out there now. Many of us can remember a time when things were very, very different.
And please bear in mind that since this an attempt at a comprehensive listing, presence on this list should not be taken as an endorsement of a maker's instruments, and the fact that several makes are listed within one category does not necessarily mean that they are of comparable quality. Before making a purchase, consider reading other concertina.net threads about particular makes or starting a thread with an inquiry of your own. If you are buying an instrument that has to be ordered in advance of construction (required for a number of makes) look for an opportunity try out an instrument of the same make before placing an order.
Student/Basic/Starter [built with accordion reeds mounted on accordion-style reed blocks]
Beschäftigungsgesellschaft Klingenthal, also known as Schaumanufaktur Klingenthal [sold under the names Silvetta, Castiglione, and perhaps others] This maker seems to have gone out of business. I'm leaving the listing here on the off chance that someone will continue where they left off.
Brunner/Stagi [formerly Bastari and sometimes sold under other brand names]
"Cheap Chinese" [sold on eBay and elsewhere under various names]
Concertina Connection [vintage/traditional-type action]: Elise Hayden Duet, Jackie/Jack English, and Rochelle Anglo
Intermediate/Mid-range [vintage/traditional-style action and general construction, but using accordion reeds which are mounted flat]
Akkordeon-Werkstatt [Also make a 10-button kit. I know very little about this maker's instruments so I'm not positive that they belong in the Hybrid/Mid-range category.]
Boorinwood Intermediate model
Danie Labuschagne [hard to categorize: makes only 20-button German-style concertinas, but with a high degree of care and skill]
Morse [Button Box]
Sherwood C-G and G-D Anglos [Hobgoblin]
Vintage/traditional construction, using concertina-type reeds
Colin & Rosalie Dipper
Edgley Heritage Model
Holmwood [Hamish Bayne]
Kensington [Dana Johnson]
Kookaburra [Richard Evans]
Wakker [Concertina Connection]
Wheatstone [Steve Dickinson]
Wifra [Willie van Wyk]
Edited by Daniel Hersh, 13 May 2013 - 09:00 PM.