So much depends upon the state. If you're in most of the southern states, the experience is much much easier. If you're in the coastal cities, it could get tough.

I would highly recommend taking a first time gun class which is offereed pretty much anywhere. It would cost about $80, and they give you practical gun info, few legal info, and concludes with class in gun range. Google the class in your area.

if you've no experience with guns, and want to practice a lot with your first gun without costing too much in ammo, then you can get a 22LR semi-auto like Ruger, P22, or buckmarks, etc. These good .22 guns are around $300 which is about half of a good 9mm guns. The price for 22 LR ammo goes for about $17 for 500 rounds.
However, 22 cal is not primarilly for the self defence. It is more for practice in range, and making you comfortable with shooting, and polishing your skill.

If you're looking for a self defence gun, and you've no experience with guns before then, I would recommend getting a 9mm semiauto. Glock 17 or 19 is a good option, so are M&P, XDs, etc. These go around theprice range of $500. The price of ammo for 9mm is about $17 for 50 rounds.

If you're looking for even more effective force of bullet, then you can go for .45 cal. However, I wouldn't recommend this higher cal, although it's popular these days. First the price of guns in 45 cal goes for over $800. Second the ammo price is about $17 for 20 rounds. Third, if you don't have any experience with guns before, then the force or recoil, the heavy feel might discourage you from carrying the gun. Also .45 cal handguns are usually large and there's few models for concealed carry. 

one thing I would like to point out is that if a person buys a gun, then he usually buys more than one gun in his lifetime. You will know what I mean later. 
So my advice to you is get like 22 cal semi auto for now. Get good practice, and be comfortable using a gun. Then you may go with higher cal for self defence. you can also keep your 22 cal, and keep it in your family for others to practice. 

@Sajhaguy69 - Very nice information and advice. Thank you so much.
By the way, I am in Northern Virginia. If you are happen to be from this area please give me some tips where I can join gun class and shooting practice.

Thanks again.

I don't live in Virginia. I know there's big NRA headquarter in Fairfax, VA where they have nice indoor shooting range facility in the basement which is open to public.There's also Gun museum in the building. I've been to the museum; it's nice, however it's a museum so only old guns. It was free to enter the museum. 

I would suggest google for instructor for frist time shooting class or concealed carry permit class (and ask for first time shooters' class).  If you can't find that in your area!, then you can visit the museum in Fairfax, VA, and they have gift shop in museum, ask the person who works there for shooting instructor (I would assume they have contacts).

I hope that helps.

 How much does an AK-47 rifle cost? 

 you can find AK-47 made by many manufacturers from different countries. A typical one would cost about $800.

why u need a gun when you havedonenothing to others?
oris it for own recreational purpose?

Kittys, some people like to keep guns in their homes to keep their family safe from intruders. Didn't your father keep a Khukuri under his mattress? My father did! 

i am hearing this for the first time, putting khukuri under the mattress, do you live in war prone zone or the place where there is high frequency of dacoits
like in indian and some nepali villagers, you gotta put two hose rifel just in case there is a dacoit enters your home

not a fan of guns though
how many sajhaiets have guns?
I have a simple pistol not complicated  bought it in walmart, just for a security as said by riddle

when whole america is shouting for gun control and u guys are tempted to buy one
ridiculouslyyy funny

Jaimatadi, before you were born, Kathmandu that you see today was nowhere as populated. In fact, the place that I grew up at wasonly accessible by motorbikes and bicycles (five-ft road). There were very few houses and the location of our house used to be called 'faant'. Dhaan baris were found in abundance and as were thugs/chors. When I was growing up, my house was broken into 5 times during that time. Since my dad was in the armed forces, I always wondered why he didn't keep a gun and/or shot 'em off! 

Funny how things change in 15-20 years. We bought the total piece of land for under 50k (total) back then and built a house. The price of same piece of land has inflated to 50 lakh/ana. 

 AK-47 for home defense is little much I suppose, 
You've to always care about what's behind the target, or incase if you miss a target. If you use AK-47 or AR-15 type, chances are that bullets might hit someone else who live in another room or another house close to you. 
Shotgun would be a fair option for home defense. Shotguns usually have lower range but higher effective target area. Also the sound of pump action would deter and sure would scare any intruder, just FYI.

 I never implied that I wanted AK-47 for self defense, did I? You can fend off an intruder with a Khukuri, let alone a firearm. 

@wiscon,

What model did you buy? I am bit confused which one to buy for best home defense. I am thinking of Glock 21. Any advice?