While trying to tidy up my Picasa albums i by mistake deleted some photos instead of just removing them from Picasa,Are these lost forever. Please say no
Providing you have not deleted a lot of other stuff they should still be in your Recycle bin.
Double click to open and highlight the once you want to retrieve by clicking on each one while holding the Ctrl key down. Then on the left click the 'restore this item' and the images should all be back where they were deleted from.
Sounds like a good time to back up your photos (and other important files) to CD or DVD.
It is so easy to delete an important fi;le (as you have found), a computer or hard disk can easily crash, leaving all your data lost, or a computer or laptop can easily be stolen in a burglary or from a car.
EVERY important personal file on your PC should always be backed up to at least ONE CD or DVD, maybe TWO CDs or DVDs to be totally safe.