Here are a number of links that you may find useful.

IEEE and official Organizations :
   http://www.eda.org
   http://www.accellera.org
   http://www.systemc.org
   http://www.systemverilog.org

Free HDL , Prototyping & other links :
   http://www.opencores.org
   http://tech-www.informatik.uni-hamburg.de/vhdl
   http://www.cmosexod.com

Doulos Know-How section :
   http://www.doulos.com/knowhowframe.html

Cool Hardware (we tried and loved !) :
  http://www.rockylogic.com/index.html (cheap & handy Logic Analyzer !)
  http://www.fpga.nl (Marco’s site with Twister Altera board & Lancelot extension).
  http://www.seytronix.com (Xilinx board + high speed Spartan II based scope)
  http://www.ftdichip.com (great USB chips, perfect FPGA companions !)
  http://www.ftdichip.com/dlpusb1.htm (ready-to-use USB module)

Tcl/Tk :
   http://www.tcl.tk/
   http://www.activestate.com

Ben COHEN :
   http://www.vhdlcohen.com

GNU EMACS Editor and VHDL mode :
   http://www.gnu.org/software/emacs/windows/ntemacs.html
   http://opensource.ethz.ch/emacs/vhdl-mode.html

IP Measure of Reuse Excellence :
   http://www.openmore.com

Some VHDL Simulation Products :
   http://www.symphonyeda.com (excellent and affordable VHDL simulator)
   http://www.model.com
   http://www.aldec.com
   http://www.acc-eda.com

Some VHDL Synthesis Products
   http://www.exemplar.com
   http://www.synopsys.com
   http://www.synplicity.com
   http://www.acc-eda.com
 

Some FPGA/CPLD Vendors :
   http://www.actel.com
   http://www.altera.com
   http://www.atmel.com
   http://www.latticesemi.com
   http://www.quicklogic.com
   http://www.xilinx.com