If you need big TCAM, then you'll definitely go for a dedicated chip - don't try to implement in PLD.
Small TCAM's can be implemented in Lattice's XPLD and ORCA4 (see Apps Note on Lattice's website). They have a LPM to ease the process of implementation.
I'm not aware about other FPGA's capable of implementing TCAM's.
I am now using the FPGA of Xilinx, With the Virtex serials, you can implement CAM by means of SRL16 or BlockRAM. You can search the appnote in the www of Xilinx. In fact , I think if there are BlockRAMs in one FPGA , the we can construct CAM with it.
Go to www.netlogicmicro.com They sell CAMs. See if you can register and
download IPCAM data sheet from there. You will get lot of info in the datasheet
itself.