I'm brand new to adobe products and downloaded the 30 day free trial of adobe illustrator so that I could edit some .eps files that were sent to us by a designer and also to see if it would be time effective for us to try doing some work inhouse.
Today [about 7 days in] when I loaded up the trial it said "this is the last time that you will be able to run AI without a valid serial key" what happened to my other 23 days? can I get them back? or is that it.
can I get them back?
No, that is that. What happened is unclear, but be aware that any toying with your computer's date, installing otehr Adobe software and a number of otehr things are considered as tampering by the licensing system and thus it will shut down. So, like it or not, buying the product is realyl the only way to get it working again, unless you feel adventurous enough to do a low level format and reinstall of your entire computer....
You are not alone, you can read more about all the problems in the feedback section: http://forums.adobe.com/community/general/adobedotcom_feedback
Please read the comments of thousand of users before you spend your money on Adobe products.