i think alot will depend on why you are interested in becoming a cna. it can be an extremely rewarding job, but as with everything in nursing, it can be sad, frustrating and back-breaking. i am now an rn, but started out in nursing as an aide (not certified) just out of high school. the place i worked at trained me; it was basically an assisted living facility. i found that i became very close to some of the residents, especially the ones who didn't get many family visitors. i still have pictures of some of them hanging on my wall, and it has almost been 15 years. i learned so much from many of them. imagine being a teenager and listening to a 70-something lady telling you stories about having sex with her husband while you are accompanying her on a "smoke break" outside (they wern't allowed to smoke in the facility and i wouldn't let her go out at night alone)! she certainly corrected some of the misconceptions i had of the elderly at a fairly young age. there was also a lady who had no family. i used to take her out for pizza sometimes when i was off. i wouldn't trade my memories of that time for anything. after i went away to college, i eventually went to work for a nursing home that put me through a certification class. the residents at that facility were much sicker, though no less loveable. for many reasons, i only lasted 3 months at that facility, and left to work in a hospital as a cna, which was invaluable experience during nursing school. i also did some home care at times, so i've had a wide range of jobs as an aide, and most of them were overall positive.
on the other hand, there are many bad things to deal with as a cna: terrible pay, facilities that don't support you, nurses that don't respect you, coworkers that don't do their share, back injuries, and at times patients that hit you/bite you/pinch you. i can still remember asking the rn at the nursing home i worked at for help. she told me she didn't have to do my kind of work anymore. she was a nurse now. ideally, i would have been able to ask one of my fellow aides for help. unfortunatly, there were only 3 of us (it was a small facility), one of whom would crawl through a window in a closet every night to go to a nearby house and sleep until morning rounds. then he would change everyone once (rather than every 2 hours) so resident would be dry when day shift came on. the same nurse (rn supervisor) knew about it but said it wasn't her job to babysit. i was never assaulted by a pateint (as an aide....i have been smacked good by a few dters as an rn, though), but i know some who have been. i can remember turning, cleaning, and changing residents who weighed much more than i did, all by myself. in retrospect, i have no idea how i did it.
so, my advice to you is this: if being a cna is what you want, wonderful. we need more caring cnas that are doing the job because they want to, rather than to just collect a paycheck. i don't think you will have a hard time finding a facility that will sponser you and get you certified. i don't think i would go for a certification class that doesn't have clinical time, though. besides, there really isn't much of a reason to pay for the class yourself when you can usually find a facility to sponser you. but i would volunteer at a facility first, so you can see first hand what kind of environment you will be working in. also, choose facilities carefully. cnas are so in-demand that you can be picky. ask around. check out their record with the state. whey you go in for your interview, interview the facility back. ask them about staffing, call-ins, turnover, problems they have had. (of course, you would want to ask some positive questions, too...) most importantly, talk with some of the aides that are working there. what kind of attitude do they have? there are good facilities out there.
good luck to you. i hope it all works out.