npaden,
You really need to fertilize. Trying to get out cheap without the fertilizer will bite you in the butt in the long run. Why do all that work and half-arse it? Without fertilizer the wheat will come up and grow, but it's nutritional value will be low and the deer will be able to tell, they'll avoid it. Just like cattle will always pick a fertilized pasture over a non-fertilized one, deer will do the same with a food plot.
We plant about 100 acres of food plots all total every year. We use about 60% oats, 30% wheat, and 10% ryegrass, mixed into one of those rental spreader buggies from the co-op with the appropriate amount of fertilizer. We just pull the buggy to our place and start spreading, everything's pre-mixed by the co-op so it's one pass and go. We have the plots well disked before planting then make another pass with the disk after spreading the seed. I used to not disk in the seed and to be honest, I can't tell any difference between covering it with the disk and just leaving it uncovered, it comes up well both ways. If you choose not to disk it in, try and plant just before a rain, the rain will push it into better soil contact.
I have one of the seed spreaders like you're getting, they work good and will throw about a 30' wide pattern depending upon how fast you have your PTO set. If you do run fertilizer through it, make sure you wash it out real good and spray it down with some diesel fuel before you put it away for the year. If you don't, it'll be rusted up next year when you get it out. Don't ask me how I know.