I was in the same boat a few years ago. I looked at reviews online and bought a Kenmore from Sears for around $90. It is super-basic mechanical, but I learned how to sew on it. It look a lot of user error and never was fussy with me like a computerized machine can be. Last year I bought a $800 machine with bells and whistles, but kept the Kenmore as a backup. I don't feel like I wasted money since I got 2 years of sewing for $90.
Good luck!