Getting started with an LPC1313 Microcontroller
In general, I would highly recommend getting a development board. The LPC Xpresso stuff is very cheap, and has a build in method to program the chip, for example, here is a cheap board for the LPC13xx series: http://www.nxp.com/demoboard/OM11048.html

With that being said, if you want to 'go it alone', the way to do it is to design a bare-boards circuit that has power and the serial pins (RX/TX) going to the FTDI USB->Serial adapter. You will at a minimum need to hook up power, ground, reset, have a switch for PIO0_1 (to be able to choose between the bootloader and the application code), tie PIO0_3 to ground (for serial based bootloader), and hook up RX and TX to the corresponding pins on the FTDI adapter.

Check out document UM10375 chapter 21 (specifically 21.4) for more info on the bootloader.