Your local AutoZone or the like will have them. Also, check out Amazon as there are plenty good options there too.
I bought mine to troubleshoot an emissions problem on my bmw and have used it about a dozen times since between all my cars....very good investment. It actually saved me $1,100 at my last BMW service as I was able to prove to the mechanic that his diagnosis of my problem was incorrect which resulted in an originally quoted $1,500 job being reduced to $400! BooYah!
I have a basic scanner that I paid around $90 bucks for on Amazon. I had it for my Porsche, but the standard scanners will not handle the manufacturer-specific codes, nor allow their reset in many cases. In my case, it was the secondary air-intake check-light and the airbag light that couldn't be reset.
I have not regretted my purchase, but the fact is that it didn't do everything I wanted, so bear that risk in mind
Fair point. In this case however, the airbag was fine, but I had a legal disabler switch fitted (NHTSB paperwork) but if someone flicked the switch when hte ignition was on, it would trigger the light.