LTspice IV is a fantastic simulation program provided free by Linear Technology, one of the great IC manufacturers. This is a very good general purpose spice simulator that is unbeaten for simulating LT's switching PS chips. There is a Yahoo group for users of LTspice where you'll find many good examples and tutorials.

I use Protel for schematic capture, simulation and, PCB layout. I use older versions of Protel, if you use the current version, I suggest joining the official support list.

Check out the PCB fonts page for information on using special characters in Protel.

After designing a PCB and before sending it to the fabricator I always make sure I can read the design with both of these Gerber viewers:

Last Updated 03/30/2013 
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