Be careful about making them from conduit especially if you do not know how to weld, are a beginner welder, or are a big guy. There have been a fair number of accidents caused by poor welds and poor craftsmanship period.

Never, buy a stand from someone that make it theirself. There is a liability issue in doing so.

Your best bet is to buy a stand from an established manufacturer. Bass Pro Shops runs a huge sale right before deer season on a Strongbuilt 16' Ladder Stand for $59.99. That seems to be your best bet as a beginner.

Remember, if you buy a strap on stand, then you need to buy steps of some sort and that will add another $20.00-$40.00 depending on how high you want to put your stand.

Good luck!
Matt