If you can aford it, the LGB set is not a bad place to start! For the money you get a bullet proof engine, sturdy cars, track and a good 1amp powerpack thats good to start with.
Other good starter sets are by Aristo-Craft and USA Trains. Bachmann sets have good engines and cars but lousy worthless track for outdoors, get it as a second set after you have track down.
Now you need to ask yourself, “How big am I planning on making this layout?” If you think it will be something simple, not too big about 10 feet x 10 feet, then the 1amp pack will be fine and all you’ll need is the extra track. Anything larger than that and you will need a bigger powerpack.
Its a good idea to draw up a track plan so you know how much extra track you’ll need. and where you will need to either raise ground or cut it out if needed. Start simple, get running, then you can go insane and fill the yard with track!
I suggest a loop (final shape depending on your area) with at least one passing siding or spur. The LGB starter set will have 4 foot diameter curves. Now if you only plan on running LGB stock or only the engine that came with the set, fine, no worries.
BUT if you think in the future you’ll want to run larger engines , then you better plan on larger diameters. I would suggest in that case 6’ diameter as a MINIMUM , However If you want to run bigger steam engines like Bachmanns 2-8-0 Consolidated, Heisler, Spectrum line, or Aristo’s new DASH-9, plan on 8 foot diameter MINIUMUM. 8 foot is becomeing the Standard curve in large scale.
Also read alot , here other forums, websites, magazines, books, etc. Knowledge is power. Good luck, Vic.[8D]