How long do i have to charge a dustbuster? I purchased one at a garage sale and it does not seem to be working. The owner said that it was working..

It is surely under guarantee and should be returned to the supplier...

Does the charge light come on when you plug in the charger? If not, the charger or cord is probably bad. If it seems to charge but you're not getting as much time as you used to, the battery probably needs to be replaced. Check your warranty and call dustbuster or go online to purchase a new battery. Another alternative, especially if it is out of warranty is to take the unit to a Batteries Plus store and have them replace the battery.

I had the same issue, then i just found the manual, in charging part, it says:"The charging indicator will be lit as long as the
appliance is connected to the plugged-in
charger."
Also it says:"While charging, the charger may get warm, this is
perfectly normal and safe. It can remain on
charge indefinitely without damage or danger. It
is not possible to "overcharge" the battery cells
with the charger provided"

You can test the output of the charger with a multimeter. Set it at about the 20v scale and touch the contacts at point where it connects with the Dustbuster. If you get a reading it means that the charger is working. I would say that the charger is most likely not working because LED indicators very seldom fail while chargers are not all that reliable.

Yes the battery is most probably the problem. you can check is the voltage of the fully charge battery is same as what is stated on it, if not you definitely need a new battery

If the battery is nicad they will not tolerate leaving on charger past full charge.

I have bad news. That part is no longer available; check out the info here:
http://www.ereplacementparts.com/black-and-decker-fve9610-dustbuster-parts-c-4167_8887_8911.html
I actually have exactly this kind of dustbuster, and I was able to renew the battery pack, but I had to do it by using eight individual cells and soldering them together. The size of cell (I think it's called a sub-c) is not common to consumers, but is fairly common to battery pack manufacturers. Quite honestly, your dustbuster with no battery is worthless, even when it was available, the pack was $46.46 as a spare - probably more than the thing is worth. Buy a new one from wal mart! If you really, really want to look at getting a new pack for this one, then your only option is to find a specialist battery store (I know there's one in my city) that can 'remanufacture' them. Basically, they take the old pack, and rip out the old cells, and put in new ones. They have the special equipment to weld the connections without frying the cells too, and they have access to Sub-C cells, of course. It'll be expensive. Good luck, you're gonna need it. Sell it at a garage sale; it looks nice.

Black and Decker website offers product manuals. Also, various online vendors provided information I needed about DustBuster in product description, making it unecessary to purchase manual.

http://www.bissell.com/images/UserGuides/1719_806.pdf

download from there

Leave it in the charger for at least 7 hours and then try and see if it works on a full performance time of roughly 3 minutes.