I deleted my pictures on my computer (improperly I guess) and now when I try to reload them from the camera again, "no new pictures found" pop up apperars, and I can't open or examine the camera memory stick.

OK! If you have already cleaned these pictures off from this camera, you may try to get them all back from this computer.
Firstly, check the Recycle Bin and see whether they are there. The deleted files often not completely destroyed after the deletion process, they are only moved to a folder named "Recycle Bin". You could easily restore them back, if you see them there.
But, unfortunately, you've emptied your Recycle Bin, you also could download a PC data recovery freeware to take a chance:
http://www.freeware-fix.blogspot.com/2013/02/data-recovery-for-pc.html

In my personal experiences, this freeware is a great data recovery freeware that could easily retrieve you deleted pictures back as long as you've not overwritten them.
Note: Do not save anything new to overwrite your original pictures since then.
Always make data backups of everything important.

It looks like you've cleared you camera card as well as your PC.

You need a file recovery programme. Plenty free either google file recovery freeware or go to filehippo.com and download either "Recuva" or"PC inspector file recovery"

Just remember you have to recover to a different source than you're recovering from because you may overwrite the very files you're trying to recover.

IE :- recover from PC to USB flash drive.