There are many tools and each company uses different tool set.
But, if you are interested in FPGA design, it will be the best to start from vendor provided design package because it contains all required tools to design FPGA.
For example, Xilinx ISE, Altera Quartus-II and Actel Libero contain synthesizer, PAR, simulation tools in their packages.
There are other popular tools which are commonly used in the industry also such as ModelSim, Questa Sim, Active HDL for simulation, Synplify pro, Precision Synthesis for synthesis, etc.
I hope it helps....