Aggie, I'm assuming you got a large format enlarger, probably a 4x5. (If its an 8x10, then GADZOOKS!) I just got a 4x5 operating a couple weeks ago. Since my setup has to remain semi-portable, I mounted it on a piece of 3/4" cabinet grade plywood. The local lumber yard always has some remnants so I didn't have to buy an entire very expensive sheet. The enlarger sits on top of my roll-away toolbox, which has about a thousand pounds of tools in it, so the "table" is very stable. One can attach some small tension wires between the column top and the wall using turnbuckles. This keeps the column from vibrating.

If I didn't have to keep the enlarger portable, I would have attached directly to the wall.

A friend gave me a pretty good book on all this stuff. Its titled "The New Darkroom Handbook", ISBN 0-240-80260-8. It has some very good plans for enlarger mounting and building a projection table underneath. I highly recommend it to you. Good luck and hope your carpentry skills are as good as your photography!