Personally, I like to have both a knife and gun around for when I'm going somewhere. Of course if you do that then having an understanding of both and how they work is a duh but that's obvious. If you are willing to take the risk with cops and your everyday idiots then so long as you're in the US you can carry a handgun openly in any state besides California, D.C., Florida, Illinois, New York, South Carolina, and Texas. Many others have a level of restriction of course in either some level of permit, or where you can carry it, etc but that's all up to you in your decision making.
Long guns however open a level of option to you and there's a number of nice designs and even homemade ones that will grant you your defense intention but also can make great survival weapons to use for limited hunting or dealing with a predator. California, D.C, Illinois, Florida, Massachusetts, Minnesota, and New Jersey don't allow this but most places have little to no restriction on it outside of the obvious.
Price ranges can be a little daunting but some nicer deals exist. Personally if you're having issues or worried about cops, yet still want a bang bang for your reasons then I would recommend a flare gun with a separate subcaliber device that can be had on the previously mentioned BudK.com. Since they're flare guns and a metal tube, it doesn't count as a firearm until they're put together and can be stored separately in your pack or wherever else then the insert can be put in when needed. Hell, get a 22 one (27 bucks if I remember right) and a 45/.410 and you're set to go with a good survival/defense weapon and hey you got a nifty firework launcher too!
