Any plans to include the Eagle files for the breakout board?

Here's how to hook it up to an Arduino...check out my tutorial and sketch

any instructions/sample sketches for Arduino?

There is a useful discussion (for beginner's like me) on using this switch here, including some sample code with debouncing, etc.. The code is written for an Olimex LPC-P2148 board, and I toggle the two LEDs depending on whether the switch is up, down or depressed.
http://tech.groups.yahoo.com/group/lpc2000/message/35707

include

int main(void)
{
IODIR1 &= 0x03800000; // P1.23...25 as inputs
while (1)
{
// Check button state
if (!(IOPIN1 & 0x02000000)) // T (P1.25)
{
// Select Button Pressed
}
if (!(IOPIN1 & 0x01000000)) // 2 (P1.24)
{
// Down Button Pressed
}
if (!(IOPIN1 & 0x00800000)) // 1 (P1.23)
{
// Up Button Pressed
}
}
}