Monte, if you have the tools and skills to do it you can make your own plans. Some criteria would be helpful for a noob tho. I'm on my third bench and have helped a couple other guys make theirs, what follows are the basics of what I've learned.
Bench top:
Height- Make the top about (standing) belt buckle height so you can easily work standing. Plan to use a bar stool for sitting work. (Got mine at a garage sale)
Lenght: Make it longer than you first think. Mine is a full 8 ft and it's none too long.
Width: Make it wide enough to give a good work surface but not too wide to easily reach stuff on the back side. I like about 20-22 inches, no more.
Surface: A 3/4 seamless top - plywood or OSB with 3-4 coats of marine grade polyurethane - is plenty sturdy and easy to keep clean. (You may want to split a 4x8 sheet and glue the halves together for a really sturdy 1 1/2" thick top.)
Support framing & legs:
Legs - of 2x4 are plenty strong enough, the commonly used 4x4s are wasteful overkill since the load will be in compression. Plan where you want the presses and have a leg within 6-8" to absorb the stress of working.
Under framing - Set your underframe back at least 2" from the front and ends, that way you can "C" clamp other tools - case trimmer, etc. - to the bench top edges when you wish. And make the underframe suitable for knee/leg room when working.
Storage - you will want a lot of it, under and above the bench.
Put at least one or two full length shelves under the top to store tumbler, media, empty brass, tool box, gun cleaning supplies, chronograph, bullet casting tools/supplies, etc. Ideally, you might want to add some simple hinged doors to help keep dust down.
Build a "book shelf" unit to sit either on the bench top OR - better - mounted on the wall behind and above the top so it won't interfer with use of the top itself. And not wider than maybe 7 1/2" or you'll lose stuff on it. Keep enough room between shelves for loading manuals and powder containers, loaded ammo, etc. Make the lower shelf at least 16" above the bench top and run shelves all the way to the ceiling, supporting the shelves well enough for them to support heavy things!
Tool locations:
Presses - keep about 10" to the left and 16-18" clear space around the presses if you're right handed. And expect to block up or otherwise raise each press so you can fully depress the lever without bending over (your back will thank you). Most of us prefer to keep the presses towards the right end of our bench so we can have max use of the rest of the bench easily. Plan to attach the presses with cut lengths of 3/8" "all thread" rod so you can go completely through the top and under framing for strong attachment, use large washers underneath to reduce compresson of the wood.
Powder measure - get a good bench stand for your measure and place it behind and slightly to the left of your main press, well behind the top front edge so you can easily reach it while keeping the bench front clear for loading blocks, bullet boxes, etc.
Beam scale - Make a box or other support so the scale is between chin and nose level for easy viewing when working. Make it large enough to also support a trickler. When charging, place the scale just to the left of the measure. (That provides a convienent and smooth work flow to drop a charge, trickle it to weight, dump it in cases sitting in blocks and seat bullets without having to take a single step. Done this way, a beam works as fast as any digital for me and I have no need to warm anything up or keep adjusting it as digitals often do!)
Vise - A 3 1/2" or so swiveling "machanics" vise mounted on the left front corner will be more handy than you might think. It will help with some reloading tasks, can hold rifles for cleaning and makes a great temporary base for trimmer or concentricity gage, lubrasizer, etc, IF they are mounted on wood blocks the vise can close on.
Bits and pieces:
Paper towels are very handy. Mount a roll holder at some convienent location.
Electrical outlets for radio, phone, vacuum, clock,.. on the wall. More outlets on the bench front for drills, tumblers, battery chargers. Use electical boxes OR power strips but have more than you think you will ever need - you'll need 'em! And MUCH easier to install them when you build than adding later.
Assembly with nails is not good, use screws and glue as much as you can so joints won't work loose over time.
LIGHT! You can't very well have too much. Ideally, install dual 48" tube floresent "shop lights" directly above the full length of the front edge of the top so you will have shadow free lighting over your full work space.