Hi Kirn ,
To add to what others have posted , what you think are spaces may not really be the space character. For example , the following text :
$ 22.00
contains what look like spaces but are really a different ASCII character. In such a case , what you can do , place your cursor in any cell which contains these "spaces" , press F2 , move the cursor to one of these "spaces" and press CTRL C to copy this character. Now in your Find and Replace dialog box , in the Find box , paste ( CTRL V ) this copied character ; in the Replace box , just press Enter , and select Replace All. Check whether these "space" characters have been replaced.
Narayan