Where can I find the in-depth LPC2132 datasheet?
The latest user manual for the LPC213x family can be downloaded here in PDF format.  

Note: This is rev 02 -- the URL posted by pingswept above (no fault of his own) is the earlier rev 01 version.

Disclaimer: I consulted for NXP and the engineers inside the company are incredibly frustrated with the website organization at NXP.