If you don't have any building experience and don't own ANY tools, then it might be kind of difficult to make a guitar. But, it can definitely be done. There are tons of people who have made very nice first guitars without any experience. I actually got interested in building guitars a few years ago when I stumbled on to this site. I didn't have much woodworking experience, didn't know too much about how guitars were made, and didn't have much money to buy parts or tools. I decided that I really wanted to build a guitar and do it for cheap. I planned on buying the cheapest parts available and use minimal tools. I was going to use an old jigsaw to cut out the body and use a chisel for the cavities.
Once I started learning more about building and actually practicing with scrap wood though I figured it would be best to invest in certain tools. I ended up getting a router (you definitely need one of those I think if you want it to be easy and accurate), a bandsaw, a small drill press, and some other tools. Over the last two years I've spent about $500 on tools and could easily spend twice that on more tools. If you have money to spend, then you should invest in certain tools. But if you are patient, you can get by without spending money on certain tools (bandsaw, router)....or you could borrow tools from people.
As for the guitar parts, that is up to you. You can spend a lot of money on great wood and parts, or you can build a cheaper (slightly lower quality guitar) guitar. Some people spend well over $1500 to build a guitar, but you can make one for less than $500. I'm currently working on my second project and it will probably end up being around $500 or so for the wood and parts. THe last project I did was a bass, and here are some pricing specs that might help give you an estimate of what to expect if you want to do a cheap project:
alder body blank- $50
premade neck (with tuners) bought on ebay- $40
EMG select pickups- $45
wiring kit- $25
knobs/shielding/neck plate/etc $40
TOTAL= approximately $200
I went as cheap as I could and the quality wasn't that great, but you can see that it is possible to make a guitar for fairly cheap. As you progress you can spend more to make better guitars. For my current project I've spent almost $200 on just the wood, and I would have preferred to spend more. The total will probably be around $500 and I keep getting tools as I go along.
So....sorry this is kind of long, and I'm not sure if it helps you much. Basically I am just saying that you CAN build a guitar for fairly cheap. If you are serious and have the money though I recommend good tools. You have us here at the forum for help, so feel free to ask about where to do your parts/wood shopping and how to build guitars. Good luck with your project!