I managed to pick up a 2.0" touch screen for around $4, although the screen is on the slightly small side, it still manages to support a resolution of 320x240. Normally these type of screens are sold into a secondary market with the hope that they can be interfaced to an Arduino, their primary use seems to a PDA or home communication device given the imprinted icons (which aren't removable).
The display supports a 8 bit parallel LCD interface (using the S6D1125) along with a 4 wire resistive touch. The downside with using such a display is that it requires a large number of pins, in our case 12 GPIO pins and 2 analogue pins (for resistive touch).
The code to drive the display was built using the i.mx6sx FreeRTOS sdk.