ok. sheet styrene comes in alot of different thicknesses and types.
most of the realy thin stuff is pretty sturdy, it will snap if bent to far instead of deforming.
thicker stuff usually is what is called "foamcore" and is basically a plastic sandwich, with two very thin but rigid outer sections and a thick inner section made up of a pourous plastic which is softer but just as sturdy. This foam core stuff holds super glue REALY well and I use it on alot of my larger customs.
MOST people will go the easy rout and go to wal mart or lowes or any other home improvement store and get the cheap "for sale" signs, they are made of sheet styrene plastic.
I prefer factory grade styrene sheet because it is uniform and plain white. you can order it online from lots of different places, just do a google search for "sheet styrene plastics".
as for the blue tie fighter... idk, look at some reference pics and then pick the best color that matches it visually... I'm horrible at matching colors.
OH... and do you know for certain that the e-bay custom TCW y-wing isn't a reworked star wars transformer? If I were doing the custom I'd probably find one of the y-wings from the transformer's line, glue all the parts shut and then fill in the cracks and repaint it.... it'd be simpler that way. (although it might be slightly too large or mispropoortioned...)
