I don't know if there are any LPN programs on-line, at least not any that are accredited. I've tried looking but couldn't find any. Maybe someone else will know of one. But anyways, your best bet is to either go to a community college or a private college around your area. Community colleges usually have pre-reqs to be completed before you can even apply to the LPN program, but they are much cheaper than private colleges. I'm applying to an LPN program at a private college, and although it's a little pricey, there are no pre-reqs required- just a HS diploma, TEAS test, and recommendation letters.
And yes, many LPN programs can be done within a year. The one I'm applying to is about 12 months long, but there is another one in my area that lasts 2 years, so it depends on the school. Hope this helped you a little---and good luck!!
P.S. I think working as a CNA is great thing to do before and/or during nursing school! I'm getting certified this summer and plan on working for a year as a CNA before I enroll in LPN school. Once I start school, I'll only be working weekends so I can devote my time during the week to studying.....because I know there will be a LOT of studying to do....