I bumped into the back of someone on a car park on the morning there was no damage to mine and a little scrape near his back wheel which he said would probably just need respraying I gave him my details and when I got back home later in the day I rang my insurance only to be told it had run out a week before. I was mortified I said I didn't realise I thought it was deue in may and that id had no renewal letters etc but they said that it was march and they had sent out letters after a bit more discussion it was found that the letters had been sent to my old address as I had moved house a few months before and even though I had up dated my new details with them the letters somehow went there so I set it back up again atraight away but what do I do now regarding the accident as I can't find where I put the other partys details so I can't get in touch with the other driver to explain and offer to pay for his damage ? Do I just wait for his insurance to get in touch with me and then what happens as I waant insured at the time of the accident I'm really worried as it was a genuine mistake and I don't want to get into any trouble?

Does your state require all drivers to be insured? I'd keep working my way up the ladder with your old insurance company. Most allow for some extension especially if you get your premium in to them pronto. Remind them of THEIR error using your old address after you updated them. Ask them why you would have updated them if you were dropping their insurance.

... what do i do now regarding the accident as i can't find where i put the other partys details so i can't get in touch with the other driver ...

The other driver has your insurance information. Have your insurance company get the contact info. For you when and if the other driver contacts your company. But don't tell the other driver (or his insurance company) that you don't have insurance. Continue to pursue that angle, as Ballengerb1 has suggested. If he or his insurance carrier doesn't contact your insurance company, nothing is going to come of it.

Please use punctuation in your posts - the lack of commas, periods, etc. make it very difficult to follow your stream of consciousness.

Obviously you are responsible for damages. If you can't contact the other party I suggest that you wait for him or his insurance company to contact you. Probably what will happen is they will call your insurance company, your company will inform then that you weren't covered, and then they will call you. They should provide you with a repair estimate to back up whatever amount they want you to pay, and if you want you could counter with a lower offer if you have good reason to do so. Just be aware that if you don't pay what they ask you may be sued for the damages.

As for your temporay lack of insurance coverage - it seems like there was no police investigation of the accident so no worries. It's fortunate that there were no injuries and the extent of damage is relatively minor.