No, I would never wear scrubs unless the interviewer specifically requested that I do so!
You want to look neat and clean (no 2 inch neon green press on nails-short and natural is best...minimal makeup...nothing crazy with the hair, etc). Your clothes-no matter what you wear should be clean and ironed, and they should fit right, so try everything on 1st, because what fit last year may not fit so well this year (and on top of the negative impact on the way you look, you'll be physically uncomfortable if the waise from your pants is cutting you in half, or if your breasts are smashed by a too tight top).
You mentioned that you're desperate for a job and imply that you're financially put out a bit. My 1st interview outfit as a medical assistant was a pair of brown slacks ($5) and a white blouse ($3) from the thrift store. I borrowed my mothers shoes. When I was almost done with nursing school, I was still broke, but felt the need to really look my best to boost my confidence, so I went to Burlington Coat Factory (like a TJ Max/Marshalls, if you have any near you) and bought a really nice black pinstripe pantsuit for $29.99-it came with the pants, vest and jacket--all I had to get was the shoes and an under shirt.
As far as getting interviews--the want ads will have your best source as far as quantity. Set up a nice resume (your school may be able to help) and fax it to every where you see might need a CNA. The more places you interview at, the more options you have and you can see what you like. BUT, it's also good to ask around to people who have worked as CNAs, as they can tell you the places that you may want to avoid (too much mandatory OT, unpaid meal breaks, bad ratios, crappy pay, no benefits, high turnover, etc) as well as places you might want to seek out (good pay/benefits, staff treated well, fair ratios, etc).