I'm not an expert on unused Plus options on older PH's, but I've got some advice (for what it's worth).
Stop thinking about the lost tickets for awhile and tell yourself that your subconcious will come up with the answer.
Then after about 3-4 days of searching rest, start to think of all the strange places you keep things. Go through all of your old WDW paperwork from your previous trips, i.e. old park maps, scrapbooks, pictures in their store pouches still, postcards, souvenirs, credit card receipts, park receipts, your hotel bill, etc.
Then search here:
+The photo album for the WDW trip
+you or your spouses underwear drawers or dresser/lingerie chest drawers (sometimes I put important stuff in there because I'll open it up everyday and see it and think I'll remember it.)
+your jewelry box/chest
+your desk drawers (maybe you were more organized than you thought and filed them away somewhere obvious)
+think about what other activities/events took place or things you purchased right around the same time that you came back from your trip - could it be in someplace related to that?
+Did you put them with other important paperwork thinking that you wouldn't forget it there, ie tax returns, car titles, birth certificates, insurance policies, etc.
+ Here's someone who has another idea a little more ethereal than mine:
http://www.spiritualwellbeing.co.uk/finding_lost_items_with_the_angels.htm
Here's an interesting site where you can post on a message board the description of the item you lost and a psychic will post (for free) his/her impressions of the item's location.
http://www.healthypages.net/forum/tt.asp?forumid=99&p=&tmode=1&smode=1
Another piece of free advice: If you can't find the tickets: Don't waste so much time and energy worrying about it. Were you planning on using it for a water park or Disney Quest? How hard would it be to give up that activity, really? There are discounted Disney Quest tickets out there too if that was your plan. How hard would it be to reduce costs somewhere else in the trip budget in order to purchase new tickets for the activities you want to do? Can you do without something in the next month or so in order to come up with the $ spent on re-purchasing the tickets?
Oh, well, I've gone on and on. Hope I helped a bit.
Love to all my DIS friends, Cheryl
If I can't find them can I get them replaced at the gates? I have heard of others being able to do this, but these were form 2001 and 2002. I have no copies of the tickets (probably in the black hole that the tickets dissapeard into) Has this ever happened to anyone else and were you able to get them replaced. I am thinking I am out of luck with them being old. 
