If you don't have a lot of money, I'd invest in a good pair of tennis shoes and try and work out outside with walks and maybe jogging. Even when it gets cold you can get a good pair of insulated pants and a running jacket -- remember when you are exercising the temp feels about 20 degrees hotter than actual temp (excluding the wind factor....if it is really really windy I stay inside!)
Another option if you already own a regular bicycle is to get a bike trainer - it holds the back wheel of your bike off the ground so you can use it as a stationary bike indoors when the weather won't cooperate. Any bike shop can help you, and they run from $150 on up depending on how fancy you want to get.
Remember that if you go the machine route, whatever you buy will need maintenence - so factor that cost in. You might try and see if a local gym will give you a free week pass, then try out their machines and see what you like best. It is all about what you think you will enjoy and what you will keep up.
Finally, if you have Time Warner Cable, they have FIT TV and an exercise on demand channel. Again the only investment you need is a good pair of shoes and maybe some hand weights and/or bands, and you get great variety. I usually DVR a few shows just to have on hand.
Remember - its not the machine that makes the woman! Congratulations on making a decision to improve your fitness and I wish you an abundant and blessed 2009!