I figure I make about minimum wage on the knives I sell. Making em beats the crap outta flipping burgers and I'll never complain. There are no wealthy knife makers; maybe a handful make a good living, and the rest of the pros work hard for a decent living. There is nothing in my life more satisfying than making knives (well, there's no
work in my life more satisfying...

) But don't expect to make money off your hobby; be happy if it's a hobby that will pay for itself - knifemaking can, and it's one of the few hobbies like that. Be happy!
Knifemaking allows you to exploit your creativity in almost infinite ways. The more creative your work is, the more value it will ultimately offer. That is not to say
flashy; there are many apparently plain knives that will blow an alert enthusiast's socks off. Creativity can simply mean perfection in unexpected ways.
You will find that "perfection" is the only standard in knifemaking. No one ever completely achieves perfection but the closer one's work is to "perfect" the better one's compensation will be. This is why I make minimum wage.

I'm workin on it.
As others have mentioned, you can make knives with very few tools; files, sandpaper, a drill...that should do it. But soon you will want to take advantage of the time and work savings of better tooling, and like Steve said, that will ever end! Oh, my... I like to say I started making knives because I couldn't afford to buy them; but the truth is I could much better have afforded buying them than making them! Yet I wouldn't trade the experience for anything. Ever.
The basic tools you will want are: belt grinder; drill press; metal cutting bandsaw; misc hand tools; lots and lots of abrasive paper and belts. The skills you need are simple: Basic hand-eye coordination and patience. When Chris said you need patience, he said it in a rather understated manner, but this cannot be overstated. "Perfection" is approached only through patience. The more knives I make, the longer they take. And I'm only worth minimum wage (on a good day!).
If any of this discourages you or sounds boring, be happy as a collector! Good knife collectors are truly rare, and are appreciated. And few can afford to be both collector and maker!
Have fun, and welcome to the greatest community there is.
Dave