well it was the same problem for me…
i always wanted to play guitar, but i couldn’t afford 900USD for a good guitar(i used to think only expensive guitars are good, but now i know it’s wrong) then i started to practice on a tennis racket (i used to play tennis when i was kid) it was like this for a month and i was always hearing songs and acting on the racket as if i am playing! then i saw a guitar Yamaha C40 only 60USD (second hand) and i got it and i started to learn by myself, after few months i saw a teacher and when i played for him he said i play good but with a lot of problems and mistakes (becoz of learning by myself) it was 6 years ago and now i have a very good guitar Antonio Aparicio Aparicio AA10 and i play professionally…
to answer your question well it depends where you live and is there any musical shop close to your home?
you can get a cheap guitar like the one i got first:
http://www.amazon.com/Yamaha-Full-Nylon-String-Classical-Guitar/dp/B00004UE2D
it’s made for beginners and trust me it’s so much powerful.
you can find a second hand guitar too,but get one that is NOT broken or very very very old…
the first thing you need is the guitar itself… then you can search in youtube, there are thousands of teaching guitar videos that are very simple and you can watch and learn and play at the same time…
but don’t worry you don’t need the best teacher or guitar in the world to be able to play good 