Rainman, I haven't seen where you stated the size layout that your talking about. As Kennedy has already said, for a smaller layout you don't need a lot of complicated wiring schemes with power blocks, boosters, and etc. As stated: two wires-two rails.
If you are talking about something larger than a 4x8, then I would go along with what others have said and run common bus wires (12-14 gauge) for each power output then feed your rails from them with about 20-22 gauge wire every 6-9 feet.
For large layouts, many like to divide them into power sections (blocks) with circuit breaker protection. This serves two purposes: when there is a short, you will know which block has it by the breaker number and only that section is affected, and if you expect a lot of locomotives to be running it is easy to divide the power to the layout by adding a booster for other sections.
Personally, I would suggest that you not buy a booster until you see that it is needed. I run a Super Chief 8 amp system with ~1000feet of track and don't need one. All this hype about voltage drop from the rails is grossly exaggerated and is minimized by all the parallel connections that are made through the busing/feeders and by the track, as mentioned by NZRmac. More important is good clean connections to minimize distortion of the DCC Signal.