I too have a 2x3 speed graphic, and use Ilford 2x3 film, Tri-x sometimes is available in 2x3 still too.(posted 9268 days ago)I have two ways I can develop my 2x3 sheets (if you can call them that!). One is a large (5" diameter) stainless steel can with an adjustable height sheet holder inside. It can hold 2x3 or 3x4 or even 4x5 sheets, but I only use it for 2x3. I don't know who made it or even if it's still being made. You load it in the dark, put the lid on, then process just like you're doing roll film.
The second way, is to use 2x3 film hangers, yes they were made, and can still be found. I've seen some on ebay (http://www.ebay.com/) recently, but most of mine I picked up at photo stores, antique malls, or garage sales.
Hope this helps, Andy.