BTDT,
do yourself a huge favor...
before you do anything else, get the tax forms needed to PAY your local/state/federal business taxes over a full year.
fill them out using your projected first year earnings.
take a hard look at how much tax you'll have to pay, it will surprise you.
Divide your net profit by the number of hours required to produce your product, market it, sell it, etc, etc. you may find you'll be earning less than $1 per hour. Don't you have more enjoyable things to do than earning chump change while paying lots of your hard earned $$ to tax agencies?
might be a lot happier not becoming an official business, and just selling to friends. Your profits will be substantially higher.
And I hope you have pretty lenient zoning codes in your residential area.
As for starting a woodworking business to also acquire NFA weapons, goooooood luck getting the IRS to approve that deduction. You'd best ask first. they may not call you on it for several years, but when they do, you'll also pay interest and penalties, and on a 10K refused deduction, your gonna get raped for probably 20K. I've wasted about a hundred hours dealing with IRS idiots. Common sense is never EVER used in place of an agent's best guess interpretation of incredibly confusing regulations. It is really a bizarre experience trying to communicate with these people.
Now, if you were to sell wooden replica guns, to be used as training aids for LE/military/etc, you might be able to justify buying the real weapons, because exact measurements and weights are needed to produce your product.