What follows is some real world common sense been there, done that, skating along the edge closer to economy advice... Some of you that are faint of heart may want to skip this one.
Take this for what it's worth and use common sense to adjust it where needed to be safe.
First is the easy part. Go to Lowes if you have one and spend $25... They carry a very good book called "Wiring a House" by Rex Cauldwell. Described as "For Pros, By pros". It presents about everything you need to know by presenting the NEC in an easy to understand format talking about not just what code is but even more about why code is what it is... My copy is a little older (4th edition) but the one I recently bought my son was the 5th edition. It's the same book but has an added chapter covering protecting modern electronic devices.
While the author does from time to time recommend wiring "above code" in certain cases, he is not big on foolishly wasting money on the unneeded over-kill sometimes common to amateurs with money to spend.
If you need to keep cost as low as absolutely possible then you need to understand the basics so you can make an educated decision on where you can shave a little and where cutting a corner might be too risky. I have dozens of wiring books in my library , some recentish and some dating back to the 1950's. This one is better than all of them put together as far as conventional house wiring goes.
I started learning to weld about 1954 and building farm and shop electrical equipment about the same time. One of the great things about the old 4-H electric program of those days was that if you pushed the edge of the program over about 10 years you could have a number of decent long lasting powered shop tools.
About 1954 my father was selling Lincoln welders and held company sponsored basic stick welding adult classes. In the late 1950's he and I conducted the city high school adult education welding program. Most of the classes were farmers and contractors. I also worked with the adult machine shop classes. I really loved working with adult education programs, "everybody" wanted to learn all they could, unlike many of the high school students.
As far as wire gauge goes read this thread, especially post #9:http://www.tractorbynet.com/forums/welding/221222-lincoln-225-amp-welder-extension.html
If you look at new 225 amp buzz-box stick welders (common at farm stores) you will be surprised at how light the input power cord really is even though it has that big 50 amp "range" plug on it.
A note on the 10 gauge extension cord... Do not run 10 gauge for it and enclose it in a wall or similar. It must be exposed to open air to avoid heat buildup. My welder runs on 6 gauge wire but 8 gauge would run it fine as long as you are not spending hours trying to weld at maximum amperage. Base model welder manuals will always warn you about observing "duty cycles".
Remember that the ground wire of the power feed is just as important as the hot wires for safety. If you can do so without ringing any bells or setting off alarms you might want to check with someone (do you have any local electrician friends?) to see if your local codes (not NEC) have any odd-ball special handling of grounds etc. different from NEC.
I can't wire in a service in this county without having a licensed electrician sign off on it (but farmers do usually get a lot of leeway on farm buildings as long as you don't do sloppy work). In the next county over I can wire about anything legally. That county has been so poor for quite a while that they don't even have an electrical inspector any more. When I recently replaced the breaker box in the rental house I just called the power company and they came out and pulled the meter and opened the breaker at the transformer. After I was done I called them again and their one guy who "sort of" inspects stuff came out, looked at the box, complimented me on it, and connected it back to them. No permits, nothing.