I haven't found suitable install instruction for drupal 7 .
Huh? Google for "civicrm install drupal 7" and the first 3 results are how to install on Drupal 7.
I have installed civicrm on my home pc but cannot find where to change the currency. The recommended: http://wiki.civicrm.org/confluence/display/CRMDOC40/CiviCRM+Localisation
On the top of that page is a note:
This documentation refers to an older version of CiviCRM (3.4 / 4.0). The current stable version is 4.1. Please introduce all documentation changes and new material here.
The correct page is
http://wiki.civicrm.org/confluence/display/CRMDOC41/CiviCRM+Localisation
but anyhow you are correct that's outdated.
as with most tutorial sites seems to be drupal 6 oriented and not yet updated. There are no Global settings in Drupal 7 other than CKeditor and these do not relate to civicrm.
No, it has nothing to do with Drupal 6 or 7. CiviCRM works the exact same on both. The wiki page says to go "Administer » Configure » Global Settings » Localization" which is wrong, but if you will look in the Administer menu you will find a Localization Settings option. In there, there is a Languages, Currency, Locations menu item. I don't think that's hard--if you read the menus it's actually pretty easy.
But of course the "Administer" menu is the one inside of CiviCRM, not the Drupal one. You must click on CiviCRM to see this menu.
HTH
Fred