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https://www.amazon.com/Make-Your-Own-El ... 0953104907Hiscock takes you thru both selecting wood and the tools necessary, as well as finishing and wiring your guitar. He talks about geometry which is critical to making it play well and safety in your shop.
He has chapters building guitars with three different kinds of construction - set necks like a Gibson, screw on necks like Fender uses, and a through neck like some basses have. His example of the screw on neck is a telecaster clone which probably is the easiest electric guitar to build.
You do have most of the shop tools that you'll need - for solid body electrics I use a band saw to cut the shape, routers for the cavities and edge of the body. A drill press is pretty important for holes that must be carefully aligned and perpendicular - you can do it with a hand held drill motor but I prefer a drill press. Be warned that some less expensive drill presses are not deep enough for the holes near the bridge - particularly the ones for the strings going thru the body.
Necks are kind of a special part of the build - I rough shape mine on a band saw and do all the final shaping with hand tools (chisels, planes, spoke shave). Depending on the kind of truss rod you'll need either a router, router table or table saw to make the channel. You will need some sort of hand miter box for doing the frets or a special jig that works with your table saw (an option here is to buy a pre slotted fretboard, that is a critical component).
The other tools that you need are specialized lutherie tools for fretting, making a nut and doing the setup. You'll need a small soldering iron and a bit of experience using it.
Finish depends a lot on what you have available, what you have worked with before and what effects you want with your choice of wood. Finishing is often one of the most difficult parts of home building - we simply don't have the materials and equipment that the pros use. Finishes can range from what I call "furniture finish" (tung oils, various wipe or brush on products from the hardware store) to TruOil (a polymerized tung oil designed for gun stocks) to rattle cans of lacquer (a good option) to full on sprayed finishes. The important thing here is to not get over your head trying some sort of fancy finish that you don't have the skill or experience to pull off.
I haven't addressed wood choices - you've mentioned several that will work well. There is a good reason Fender uses alder and ash - they are inexpensive, work well, can look pretty good, are moderately light weight (important). Mahogany is the choice for most Gibson style guitars, some people use basswood because it is so light but it scratches and dents easily. I have built funky telecaster clones out of 100 year old pine barn wood - they sound just fine. I happen to be one of those people who thinks that the contribution wood makes to the tone is very small (when compared with electronics) but others feel more strongly about it.
The best neck woods are maple, mahogany or Spanish cedar - you want stability, moderately light weight and the ability to carve it with hand tools.
Here is a telecaster style guitar built from some old barn wood. I used a commercial neck on this one, most of the time I make my own. However this should give you a general idea of what you are getting in to
http://www.harmonycentral.com/forum/for ... barncasterGood luck, keep us posted