[villagetinker]

Now I know you asked for a reference for someone to do this. I do not have any references, and in the past, I was never able to find anyone interested in doing this type of work due to all of the possible problems.

IMHO, if you are thinking about going to a darker finish, you may have significant problems, as the wood was sealed with the original finish. It would require a significant amount of work to get beyond the sealed wood, and where ever you do not, you will have a lighter color. I have had very good results with Minwax Polycoat, which is a stain and finish in one product. You will still need to carefully prepare the wood to get good results.

If you table has a leaf, and you are lucky that the leaf was finished on all sides, you can test the Minwax on the bottom, for color, etc. Also, once you have the basic finish and color you want, Minwax has spray polyurethane that is very tough, and will give you a very smooth finish (flat, semigloss, or gloss).
I hope this helps, and I hope you find someone to finish your furniture. Feel free to drop me a PM if you want to discuss further.