In the UK, a bird table is generally taken to mean a platform, about 1 foot square, mounted on a pole to raise it about four feet off the ground. From this basic design, you can really go anywhere your desires take you - for a superb example, check out the picture of Gaye Horn's feeding station in the Gallery. The only no-no is incorporating a nesting area (nest box) - it may seem like a good idea, but should any bird take up residence, the table becomes part of its territory, and it'll wear itself out chasing away all the 'intruders' who come to feed there. Food can be placed on the surface of the table, or supplied in feeders (seed or peanut, or both) attached to the underside of the table. A birdbath can also be incorporated, for drinking water in cold weather as well as for bathing, and a peaked roof over the table will keep some of the rain off. Cleanliness is vitally important - you should try to wash down the surface at least once a week with boiling water, and don't let food go mouldy on the table. If your feeders are not being emptied rapidly, don't fill them so full until the birds have learnt to come and eat in quantity. When re-filling feeders, always throw away any seed or nuts that have gone mouldy, and again wash them in boiling water.
HTH
Tony