What you need to understand is that perspiration itself does not smell it is odorless. However, your armpits are warm, not well circulated with oxygen, and when wet... Bacteria will grow quickly and smell. This goes for all high-odour parts of your body. (i.E. Feet with socks on, genitila area, etc.)
what it sounds like is that you have a bacteria problem (very common). Once you perspire, the bacteria begins expanding rapdily and making the bad smell. Most deoderants will not help much in your case, as they are designed to mask odour, and anti-perspirants are designed to stop you from perspiring. (clogging your pores basically)
what you need is a good anti-bacterial soap and you need to wash your whole body down, top to bottom a few times in a day. You also need to ensure your clothing is bacteria free... Washing in the machine isn't going to accomplish this... Although most bacteria will die while in the dryer. You will need to wash the armpit areas of these clothes prior to washing them.
Once this is done, use a good deoderant like mitchum for women which is also anti-bacterial.
Hope this helps,
justin