You might like ZWCAD. They have a free demo. It was only 2D when I tried it last year. It works fine for the price. The only drawback was that I couldn't write my own arx / macro files which slowed me down.
http://www.zwcad.org/ -------------------------------------------
Lezley Barclay
Lezley Jerome Barclay, AIA
Reno NV
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